Thomas Herbert, 8th Earl of Pembroke, 5th Earl of Montgomery (c. 1656-1733), was a British politician during the reigns of William III and Anne.
From 1690 to 1692 he was First Lord of the Admiralty; then he served as Lord Privy Seal until 1699, being in 1697 the first plenipotentiary of Great Britain at the congress of Ryswick .
On two occasions he was Lord High Admiral for a short period; he was also Lord President of the Council and Lord Lieutenant of Ireland, while he acted as one of the Lords Justices seven times; and he was president of the Royal Society in 1689-1690.
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In Commission
| width="40%" style="text-align: center;" |Lord Privy Seal
1692–1699
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The Viscount Lonsdale
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The Duke of Leeds
| width="40%" style="text-align: center;" |Lord President of the Council
1699–1702
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The Duke of Somerset
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The Duke of Somerset
| width="40%" style="text-align: center;" |Lord President of the Council
1702–1708
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The Lord Somers
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The Duke of Ormonde
| width="40%" style="text-align: center;" |Lord Lieutenant of Ireland
1707–1708
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The Earl of Wharton
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HM Queen Anne
| width="40%" style="text-align: center;" |Lord High Admiral
1708–1709
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The Earl of Orford
(First Lord of the Admiralty)
