Complex sentence: Furious, junior Tories led by the Duke of Beaufort asked for French help in restoring James to the British throne while the Association (a Scottish Jacobite club) made a similar request but for the throne of Scotland and the dissolution of Union.
Split into simpler sentences: Furious, junior Tories led by the Duke of Beaufort asked for French help in restoring James to the British throne. At the same time the Scottish Jacobite group known as the Association made a similar request but for the throne of Scotland and the dissolution of Union.