Macnamara was born in London and came from a branch of an old Milesian family said to have been descended from the ancient admirals of Munster.
Macnamara soon came to regard his return as ‘a false step’, feeling that he would be regarded as insufficiently radical by the repealers of Ennis, and as too advanced a reformer by more moderate Liberals. While he approved of O’Connell’s National Council, he was unable to attend its meeting in Dublin in January 1833, and failed to vote for O’Connell’s amendment to the address, 8 Feb.
Although it was regarded by some as ‘a singular thing’ that an officer in active service had entered parliament ‘for the purpose of enforcing a repeal of the Union’, Macnamara purchased command of a troop of the 8th Hussars in October 1833.
After helping to establish a branch of the Agricultural and Commercial Bank at Ennis in December 1834, Macnamara retired at the 1835 general election.
Macnamara inherited his father’s estate of more than 15,000 acres in county Clare in 1856, settling at Ennistymon in 1863, where he earned a reputation as ‘a liberal, genial, and paternal landlord’. A ‘honourable and high-minded’ member of the county gentry of Clare, Macnamara died at his residence in Park Lane, London, in June 1873, where he had been staying for two months prior to his demise, his health having been for some time failing ‘more from the natural decay of nature than from any special disease’.
