Alexander was one of eleven children (the fourth child and first son) of a family of merchants of Scottish origin who had settled in county Donegal in the early seventeenth century. In the 1650s Andrew Alexander obtained a grant of land at Ballyclose, county Londonderry and Alexander’s grandfather, John, was a successful Belfast merchant and mill owner. Alexander’s father sold Ballyclose and purchased the lands of Milford, county Carlow in 1790, where he established one of the largest flour mills in Ireland, which by the 1830s had an annual turnover of £195,000.
In 1843 Alexander inherited ‘the great establishment’ built up by his father at Belfast and Milford,
As a resident proprietor, Alexander backed Horace Rochfort, an ostensibly Liberal candidate, for County Carlow in 1830, but supported the Conservative, Henry Bruen, in subsequent parliamentary elections.
Alexander declared that he had ‘no private ambition to gratify in becoming a member of parliament’, and stated that he ‘would not give a factious opposition’ to the government.
Regarding the conduct of the Crimean War, he opposed the ministry’s enlistment of foreigners bill, 19, 22 Dec. 1854, supported John Roebuck’s motion for a select committee into the condition of the army, 29 Jan. 1855, which led to the demise of Aberdeen’s ministry, and then opposed Lord Palmerston’s ministry by supporting Disraeli’s critical motion on the prosecution of the war, 25 May, as well as those of Austen Layard and Vincent Scully regarding administrative reform, 18 June, 10 July. He divided in favour of Roebuck’s motion of censure on the cabinet, 19 July 1855, and voted against the government’s proposal for the Turkish loan, 20 July. The following year he supported motions criticising the government over the fall of the Turkish fortress at Kars, 29 Apr., 1 May 1856. Declaring himself in favour of ‘general retrenchment’, Alexander supported Disraeli’s effort to secure the eventual abolition of the income tax, 23 Feb. 1857, and voted against Locke King’s motion to equalise the borough and county franchises, 19 Feb. 1857.
Alexander was defeated by the Liberal, Sir John Acton, at the general election in May 1859. He came forward again in 1865, when he was portrayed by the Irish nationalist press as ‘the candidate of the Orange ascendancy faction’, and was defeated by an advanced Liberal.
