Pre-1970

Sinn Féin was founded on 28 November 1905, when, at the first annual Convention of the National Council, Arthur Griffith outlined the Sinn Féin policy. That policy was "to establish in Ireland's capital a national legislature endowed with the moral authority of the Irish nation" Sinn Féin contested the Leitrim North by-election of 1908 and secured 27% of the vote.Thereafter, both support and membership fell. At the 1910 Ard Fheis (party conference) the attendance was poor and there was difficulty finding members willing to take seats on the executive.

In 1914, Sinn Féin members, including Griffith, joined the anti-Redmond Irish Volunteers, which was referred to by Redmondites and others as the "Sinn Féin Volunteers". Although Griffith himself did not take part in the Easter Rising of 1916, many Sinn Féin members, who were also members of both the Volunteers and the Irish Republican Brotherhood, did. Government and newspapers dubbed the Rising "the Sinn Féin Rising".^[11] After the Rising, republicans came together under the banner of Sinn Féin, and at the 1917 Ard Fheis the party committed itself for the first time to the establishment of an Irish Republic. In the 1918 general election, Sinn Féin won 73 of Ireland's 105 seats, and in January 1919, its MPs assembled in Dublin and proclaimed themselves Dáil Éireann, the parliament of Ireland. The party supported the Irish Republican Army during the War of Independence, and members of the Dáil government negotiated the Anglo-Irish Treaty with the British Government in 1921. In the Dáil debates that followed, the party divided on the Treaty. Anti-Treaty members led by Éamon de Valera walked out, and pro- and anti-Treaty members took opposite sides in the ensuing Civil War.

Pro-Treaty Dáil deputies and other Treaty supporters formed a new party, Cumann na nGaedhael, on 27 April 1923 at a meeting in Dublin where delegates agreed a constitution and political programme. Anti-Treaty Sinn Féin members continued to boycott the Dáil. At a special Ard Fheis in March 1926 de Valera proposed that elected members be allowed to take their seats in the Dáil if and when the controversial oath of allegiance was removed. When his motion was defeated, de Valera resigned from Sinn Féin and on 16 May 1926 founded his own party, Fianna Fáil. With the success of Fianna Fáil, support for Sinn Féin fell to pre-1916 levels. An attempt in the 1940s to access funds which had been put in the care of the High Court led to the Sinn Féin Funds Case, which the party lost and in which the judge ruled that it was not the direct successor of the Sinn Féin of 1917. At the 1959 general election, the Sinn Féin vote dropped almost 60% from the 1955 number of 152,000 to 63,000. In the 1960s, Sinn Féin moved to the left, in line with the changing policy of the IRA. It became involved in campaigns over the provision of housing and social services during the sixties (in one case Joe Clarke, a veteran of the Easter rising was ejected from a function honouring the 1916 rising, as he had interrupted DeValera's speech with criticisms over Fianna Fails poor provision of housing). It also adopted a "National Liberation Strategy" which was the brainchild of Roy Johnston. In 1967 the Garland commission was set up to investigate the possibility of ending abstentionism. It's report angered many within the party, notably Seán Mac Stíofáin and Ruairí Ó Brádaigh.

1970-1983

The Sinn Féin party split in two at the beginning of 1970. At the party's Ard Fheis on 11 January the proposal to end abstentionism and take seats, if elected, in the Dáil, the Northern Ireland Parliament and the Parliament of the United Kingdom was put before the members. A similar motion had been adopted at an IRA convention the previous month, leading to the formation of a Provisional Army Council by Mac Stíofáin and other members opposed to the leadership. When the motion was put to the Ard Fheis, it failed to achieve the necessary two-thirds majority. The Executive attempted to circumvent this by introducing a motion in support of IRA policy, at which point Ó Brádaigh led a walk-out from the meeting. These members reconvened at another place, appointed a Caretaker Executive and pledged allegiance to the Provisional Army Council. The Caretaker Executive declared itself opposed to the ending of abstentionism, the drift towards Marxism, the failure of the leadership to defend the nationalist people of Belfast during the 1969 Northern Ireland riots, and the expulsion of traditional republicans by the leadership during the 1960s. At the October 1970 Ard Fheis delegates were informed that an IRA convention had been held and had regularised its structure, bringing to an end the 'provisional' period. By then, however, the label "Provisional" or "Provo" was already being applied to them by the media. The opposing, anti-abstentionist party became known as Official Sinn Féin.

Initially, because the "Provisionals" were committed to military rather than political action, Sinn Féin's membership was largely confined, in Danny Morrison's words, to people "over military age or women". A Belfast Sinn Féin organiser of the time described the party's role as "agitation and publicity". New cumainn (branches) were established in Belfast, and a new newspaper, Republican News, was published. Sinn Féin took off as a protest movement after the introduction of internment in August 1971, organising marches and pickets. The party launched its platform, Éire Nua (a New Ireland) at the 1971 Ard Fheis. In general, however, the party lacked a distinct political philosophy. In the words of Brian Feeney, "Ó Brádaigh would use Sinn Féin ard fheiseanna to announce republican policy, which was, in effect, IRA policy, namely that Britain should leave the North or the 'war' would continue". Sinn Féin was given a concrete presence in the community when the IRA declared a ceasefire in 1975. 'Incident centres' were set up to communicate potential confrontations to the British authorities. They were manned by Sinn Féin, which had been legalised the year before by Secretary of State, Merlyn Rees.

After the ending of the truce, another issue arose - the political status for prisoners. Rees released the last of the internees but introduced the Diplock courts, and ended 'special category status' for all prisoners convicted after 1 March 1976. This led first to the blanket protest, and then to the dirty protest. Around the same time, Gerry Adams began writing for Republican News, calling for Sinn Féin to become more involved politically.During the 1981 hunger strike, striker Bobby Sands was elected Member of Parliament for Fermanagh and South Tyrone with the help of the Sinn Féin publicity machine. After his death on hunger strike, his seat was held, with an increased vote, by his election agent, Owen Carron. These successes convinced republicans that they should contest every election.Danny Morrison expressed the mood at the 1981 Ard Fheis when he said:

"Who here really believes we can win the war through the ballot box? But will anyone here object if, with a ballot paper in this hand and an Armalite in the other, we take power in Ireland?".

This was the origin of what became known as the Armalite and ballot box strategy. Éire Nua was dropped in 1982, and the following year Ó Brádaigh stepped down as leader, to be replaced by Adams.

1983 to present

A split occurred in 1986 over whether or not to end its policy of abstentionism and to allow elected Sinn Féin Teachtaí Dála take their seats in Dáil Éireann. This led to the formation of Republican Sinn Féin.

Multi-party negotiations began in 1994 in Northern Ireland, without Sinn Féin. The Provisional IRA declared a ceasefire in the autumn of 1994. The Conservative government had asked that the IRA decommission all of their weapons before Sinn Féin be admitted to the talks, but the Labour government of Tony Blair let them in on the basis of the ceasefire.^{[citation needed]}

Good Friday Agreement

The talks led to the Good Friday Agreement of 10 April 1998 (officially known as the Belfast Agreement), which set up an inclusive devolved government in the North, and altered the Southern government's constitutional claim to the whole island in Articles 2 and 3 of the Constitution of Ireland.

The party expelled Denis Donaldson, a party official, in December 2005, with him stating publicly that he had been in the employ of the British government as an agent since the 1980s. Mr Donaldson told reporters that the British security agencies who employed him were behind the collapse of the Assembly and set up Sinn Féin to take the blame for it, a claim disputed by the British Government. Donaldson was found fatally shot in his home in County Donegal on 4 April 2006, and a murder inquiry was launched. In April 2009, the Real IRA released a statement taking responsibility for the killing.

When Sinn Féin and the DUP became the largest parties, it was clear that no deal could be made without the support of both parties. They nearly reached a deal in November 2004, but the DUP had a requirement for visible evidence that decommissioning had been carried out.

On 2 September 2006, Martin McGuinness publicly stated that Sinn Féin would refuse to participate in a shadow assembly at Stormont, asserting that his party would only take part in negotiations that were aimed at restoring a power-sharing government within Northern Ireland. This development follows a decision on the part of members of Sinn Féin to refrain from participating in debates since the Assembly's recall this past May. The relevant parties to these talks have been given a deadline of 24 November 2006 in order to decide upon whether or not they will ultimately form the executive.

The 86 year Sinn Féin boycott of policing in Northern Ireland ended on 28 January 2007 when the Ard Fheis voted overwhelmingly to support the PSNI. Sinn Féin members will sit on Policing Boards and District Policing Partnerships. There has been some opposition to this decision from people such as former IRA prisoner Gerry McGeough, who stood in the 2007 Assembly Elections against Sinn Féin in the assembly constituency of Fermanagh and South Tyrone

Sinn Féin is the largest group in the Republican wing of Irish nationalism and is closely associated with the IRA, with the Irish Government alleging that senior members of Sinn Féin have held posts on the IRA Army Council. However the SF leadership has denied these claims.

A republican document of the early 1980s states, "Both Sinn Féin and the IRA play different but converging roles in the war of national liberation. The Irish Republican Army wages an armed campaign... Sinn Féin maintains the propaganda war and is the public and political voice of the movement".

Sinn Féin organiser Danny Morrison at the party's Ard Fheis (Annual Conference) in 1981, said:

"Who here really believes we can win the war through the ballot box? But will anyone here object if, with a ballot paper in this hand and an Armalite in the other, we take power in Ireland?"

The current British Government stated in 2005 that "we had always said all the way through we believed that Sinn Féin and the IRA were inextricably linked and that had obvious implications at leadership level".

The robbery of £26.5 million from the Northern Bank in Belfast in December 2004 further scuppered chances of a deal. The IRA were blamed for the robbery though Sinn Féin denied this and stated that party officials had not known of the robbery nor sanctioned it. Because of the timing of the robbery it is considered that the plans for the robbery must have been laid whilst Sinn Féin was engaged in talks about a possible peace settlement. This undermined confidence within the unionist community about the sincerity of republicans towards reaching agreement. In the aftermath of the row over the robbery, a further controversy erupted when, on RTÉ's Questions and Answers programme, the chairman of Sinn Féin, Mitchel McLaughlin, insisted that the IRA's controversial killing of a mother of ten young children, Jean McConville, in the early 1970s though "wrong", was not a crime, as it had taken place in the context of the political conflict. Politicians from the Republic, along with the Irish media strongly attacked McLaughlin's comments.

On 10 February 2005, the government-appointed Independent Monitoring Commission reported that it firmly supported the Police Service of Northern Ireland (PSNI) and Garda assessments that the IRA was responsible for the Northern Bank robbery and that certain senior members of Sinn Féin were also senior members of the IRA and would have had knowledge of and given approval to the carrying out of the robbery. Sinn Féin have argued that the IMC is not independent and the inclusion of former Alliance Party Leader John Alderdice and a British security head was proof of this. It recommended further financial sanctions against Sinn Féin members of the Northern Ireland Assembly. The British government responded by saying it would ask MPs to vote to withdraw the parliamentary allowances of the four Sinn Féin MPs elected in 2001.

Gerry Adams responded to the IMC report by challenging the Irish Government to have him arrested for IRA membership, a crime in both jurisdictions, and conspiracy.^[52]

On 20 February 2005, Irish Minister for Justice, Equality and Law Reform Michael McDowell publicly accused three of the Sinn Féin leadership, Gerry Adams, Martin McGuinness and Martin Ferris (TD for Kerry North) of being on the seven-man IRA Army Council which they later denied.

On 27 February 2005, a demonstration against the murder of Robert McCartney on 30 January 2005 was held in East Belfast. Alex Maskey, a former Sinn Féin Mayor of Belfast, was told by relatives of McCartney to demand that Maskey "hand over the 12" IRA members involved. The McCartney family, though formerly Sinn Féin voters themselves, urged witnesses to the crime to contact the PSNI. Three IRA men were expelled from the organisation, and a man was charged with McCartney's murder.

Irish Taoiseach Bertie Ahern subsequently called Sinn Féin and the IRA "both sides of the same coin". The ostracism of Sinn Féin was shown in February 2005 when Dáil Éireann passed a motion condemning the party's alleged involvement in illegal activity. US President George W. Bush and Senator Edward Kennedy refused to meet Gerry Adams while meeting the family of Robert McCartney.

On 10 March 2005, the British House of Commons in London passed without significant opposition a motion placed by the British Government to withdraw the allowances of the four Sinn Féin MPs for one year in response to the Northern Bank Robbery. This measure cost the party approximately £400,000. However, the debate prior to the vote mainly surrounded the more recent events connected with the murder of Robert McCartney. Conservatives and Unionists put down amendments to have the Sinn Féin MPs evicted from their offices at the House of Commons but these were defeated.

In March 2005, Mitchell Reiss, the United States special envoy to Northern Ireland, condemned the party's links to the IRA, saying "it is hard to understand how a European country in the year 2005 can have a private army associated with a political party".