William was born 08/Jan/1755.
He joined the 19th Foot at Gibraltar in 1769. Ensign on 26/Dec/1770. Lieutenant in 1778. Sold out 1780 in Dublin and sailed for India in the “Mount Stewart.” During the voyage, he was taken prisoner by a French and Spanish fleet on 09/Aug/1780. He was landed at Cadiz, Spain and detained at Arcos until exchanged. He sailed again from Portsmouth 06/Feb/1782 on the “Ganges,” reached Rio de Janeiro 01/May/1782 and camped there for a month. He touched at Bombay 16/Sep/1782 and arrived at Calcutta 20/Nov/1782.
Appointed Lieutenant in the Governor’s Body Troop 16/Feb/1783. Aide de camp to Warren Hastings (Governor-General of Bengal) from Feb/1784 to Feb/1785.
Married Barbara Forbes, daughter of Robert Forbes of Corse, Banffshire on 06/Nov/1788.
Went to Madras & Mysore with Lord Cornwallis Nov. 1790 and was said by his brother Thomas to have cut down a native who tried to kill his Lordship.
Invalided at Calcutta 1791, succeeded to Potterhill on the death of his brother Laurence but sold Potterhill to pay his fathers debts.
He was promoted to Brevet Captain, appointed Quartermaster of 2nd Cavalry and left Calcutta for Cawnpore 22/June/1796.
Appointed on 29/ May/1800 to command a troop in the 5th Cavalry raised at Ghazepore.
Died 03/Aug/1801 after a duel with the Hon. Andrew Ramsay brother of the Earl of Dalhousie.
Barbara Drummond Forbes
Descended from a younger son of Forbes of Corse. Daughter of Robert Forbes of Gask and sister of Sir John Forbes Drummond of Hawthornden, 1st Baronet, Commander R.N., who, in right of his wife, Mary Ogilvie of Murtle, heiress by special settlement of Mrs Barbara Drummond (only daughter of William Drummond of Hawthornden, and wife of Bishop William Abernethy Drummond) on whose death in 1789, assumed the additional surname and arms of Drummond. He was created a Baronet, 27/Feb/1828.
After William Mercer was killed in a duel in 1801. Barbara and her children moved to Scotland and lived in Perth.
She is buried at Kinnoull.
- William Mercer (b:26/Aug/1789 d:31/Mar/1791 at Burdwan.)
- Ann Abernethy Mercer (b:15/Jan/1794. m:06/Jul/1813 at Broughty Ferry, Dundee. d:1876.)
- Spouse: Charles McGrigor (b: Jul/1813. Lieutenant Colonel 70th Foot d:15/Mar/1841 at Nottingham having retired from military service.)
- Eliza Forbes Mercer (b:17/Oct/1795. m:15/Nov/1809 at Perth. d:1881.) Spouse: Richard Charles Blunt, second son of Sir Charles William Blunt, Bart. of Blunt Hall. Richard died at Bretlands House, Surrey, 16/Jan/1846 and is buried at Chertsey. His son, Sir Charles, succeeded as sixth Baronet.)
- William Drummond Mercer (b:16/Oct/1796. d:18/Aug/1871)
- Louisa Mercer (b:26/May/1798 at Cawnpore. m:23/Feb/1819. d:08/Feb/1881.) Spouse: Alexander Brodie (Manager of the Bank of Scotland, Stirling.)
- Charlotte Simpson Mercer (b:29/Jun/1799 at Cawnpore. m:30/Jun/1817. d:18/Mar/1869.) Spouse: Robert Lockhart (of Castlehill, Cambusnethan, Lanarkshire. d:02/Nov/1850.)
- James Mercer (b:18/Aug/1809. Died in infancy.)