On the death of his cousin Sir Hugh Owen, 5th Bt., in 1786, leaving an infant heir, Hugh Owen became acting head of the Orielton family interest; he was not, however, on good terms with Sir Hugh’s widow and his opposition politics were uncongenial to Orielton, although he continued to sit for Pembroke Boroughs on that interest, unopposed.
Subsequently he was not regarded as an opponent by the Treasury, though he voted against the assessed taxes, 4 Jan. 1798. On 31 Mar. 1802 he supported Manners Sutton’s motion to secure the revenue of the duchy of Cornwall for the Prince of Wales, and on 4 Mar. 1803 Calcraft’s motion for an inquiry into the Prince’s debts. In a list of March 1804 he appears as Foxite; in May as Addingtonian; in September 1804 as a follower of Fox and Grenville, but then as ‘in opposition not quite certain’ and, despite a vote against the salt tax, 4 Mar., as a friend of Pitt in July 1805. This latter volte face would be in accord with his professed ambition to secure the county for his ward, who was the natural leader of the Orange interest in Pembrokeshire. Barlow did not, apparently, vote with the minority after 1805.
He promoted local bills on roads and fisheries, 1806-8. This, together with the fact that he resided seven months a year in Pembrokeshire, ensured his popularity there, though one critic described him as ‘the merest whiffler in the world’. At the time of his death, 23 Jan. 1809, he had still not secured the county seat for Sir Hugh Owen; and the difference of opinion between himself and the Orielton family was poignantly illustrated by his will, whereby he left the remainder of his estate to the heir to the baronetcy, who was a few months later disinherited.