Richard FitzWilliam, 5th Viscount FitzWilliam

Richard FitzWilliam, 5th Viscount FitzWilliam PC (c. 1677 – 6 June 1743) was an Irish nobleman and politician. He was the only son of Thomas FitzWilliam, 4th Viscount FitzWilliam and his first wife Mary Stapleton, daughter of the English statesman Sir Philip Stapleton. The FitzWilliam family are recorded in Ireland from about 1210, and had become one of the largest landowners in Dublin. He succeeded to the Viscountcy of FitzWilliam in 1704, and became a member of the Irish Privy Council in 1715. He was elected Member of Parliament for Fowey in 1727, a seat he held until 1734. His father and grandfather had been Roman Catholics, and his father had been under attainder for a time for his loyalty to James II; but Richard conformed to the Church of Ireland.

In 1711, he built Mount Merrion House in Dublin. The older family home of Merrion Castle was, rather surprisingly, allowed to fall into decay: it was a ruin by 1730, and was pulled down later in the century. Richard spent his later years in England, but his heirs returned to Mount Merrion.

Lord Fitzwilliam married Frances Shelley, daughter of Sir John Shelley, 3rd Baronet of Michaelgrove. They had five children:

Through FitzWilliam's daughter Mary, Countess of Pembroke, the great FitzWilliam inheritance in Dublin passed into the Herbert family in the following century; they are still substantial landowners in Dublin.

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