Short answers, pulled from the story.
The initial signatories included the Earl of Argyll and his brother Colin Campbell. They also counted the Earl of Glencairn and the Earl of Morton among their number. John Erskine of Dun joined this early circle as well.
The Lords took Edinburgh in July 1559 after escalating conflicts with French forces. They withdrew under the truce terms of the Articles of Leith on the 25th of July 1559.
Their goal was to oppose the marriage of Mary Queen of Scots to the Dauphin of France. That union threatened to bring French influence into Scottish affairs and they sought to change the religious landscape of their nation.
The Treaty of Berwick in February 1560 brought an English army to resist French troops. Armed conflict centered on the Siege of Leith after Queen Regent died in June.
Gordon Donaldson explored the personnel of both groups in his 1983 work All the Queen's men: Power and Politics in Mary Stewart's Scotland. This publication analyzed the Confederate Lords who opposed Mary Queen of Scots in 1567.