Short answers, pulled from the story.
The initial signatories included the Earl of Argyll, his brother Colin Campbell, the Earl of Glencairn, the Earl of Morton, and John Erskine of Dun. These men styled themselves the Faithful and bound themselves to a radical new vision for their nation.
The Lords of the Congregation successfully took control of Edinburgh by July 1559. They withdrew under the terms of the truce of the Articles of Leith on the 25th of July to regroup and plan their next move.
The Treaty of Berwick in February 1560 brought an English army to resist the French troops. This agreement shifted the armed conflict to the Siege of Leith, which would determine the future of the Scottish Reformation.
Key figures included Archibald Campbell, 5th Earl of Argyll, James Stewart, Prior of St Andrews, Andrew Leslie, 5th Earl of Rothes, John Graham, 4th Earl of Menteith, Patrick Ruthven, 3rd Lord Ruthven, and James Ogilvy, 5th Lord Ogilvy of Airlie. These nobles worked with clergy like John Knox and Alexander Gordon, Bishop of Galloway.
The Scottish Reformation took effect in the Parliament of Scotland in August 1560. The Parliament passed acts that abolished the authority of the Pope and the Catholic Church in Scotland, replacing it with a Presbyterian system of church governance.