Seán MacManus, Sinn Féin politician, is elected Mayor of Sligo on July 3, 2000. He is the national chairperson of the party from 1984 to 1990.

MacManus is born in 1950 near Blacklion, County Cavan, and moves to London in the 1960s to find work. There he meets and marries Helen McGovern, a native of Glenfarne, County Leitrim. In 1976, he returns to Ireland and settled in the Maugheraboy area of Sligo, County Sligo, so that their family of two boys can be educated in Ireland.

Still based in Maugheraboy, MacManus is involved in Irish Republican politics since the early 1970s and is secretary of the County Sligo Anti-H-Block Committee which campaigns in support of the republican prisoners hunger strikes of 1980/81. He becomes a member of the Sinn Féin Ard Comhairle (National Executive) in 1982 and remains there for over twenty years. He is elected as the first Sinn Féin National Chairperson from 1984 until 1990. After the Irish Republican Army (IRA) ceasefire in 1994 he is part of the first Sinn Féin delegation to meet with the British government in over seventy years. He is also involved in the protracted negotiations leading to the Good Friday Agreement.

First elected to Sligo Corporation (now Sligo Borough Council) in 1994, MacManus remains until its abolition in May 2014. He is also elected to Sligo County Council in 1999 and is re-elected in 2004, 2009 and 2014. He steps down from elected politics in February 2017 being replaced by his son, Chris MacManus.

On July 3, 2000, MacManus is elected Mayor of Sligo, the first Sinn Féin Mayor in the Republic of Ireland since the beginning of the Troubles in 1969. He is also elected mayor in 2003. Sinn Féin President Gerry Adams says the election of McManus is a sign of “Sinn Féin’s rise as an active campaigning alternative in politics in the 26 counties”.

MacManus has two sons. Chris MacManus, the youngest, is also an elected member of Sligo Borough Council (1999–2014) and Sligo County Council (2017–2020) and is an MEP since March 2020. His eldest son, Joseph MacManus, was an IRA volunteer who was killed in a firefight against an off-duty Ulster Defence Regiment (UDR) soldier in Belleek, County Fermanagh, in February 1992.