Puleston began his royal service as a sewer in the chamber by 1513 and was appointed serjeant-at-arms later that year. He served in Henry VIII’s first French war as part of Viscount Lisle’s retinue. He was constable of Caernarfon Castle from 1523 until his death, and by virtue of that post, also served as ex officio mayor of the borough. He held a wide range of administrative positions including: • Sheriff and escheator of Merioneth (1533–40) • Vice-admiral of North Wales (by 1539) •
Justice of the peace for Caernarfonshire (from 1540) • Commissioner for tenths of spiritualities, coastal defenses, musters, and relief • Sheriff of Denbighshire (1542–43) and of Caernarfonshire (1543–44) •
Chamberlain of North Wales (1547) In Parliament, Puleston was elected MP for Caernarfon Boroughs in 1542 and for Caernarfonshire in 1545 and 1547. In the 1547 Parliament, he served alongside his son Robert, who sat for the boroughs. He was knighted by 20 December 1546. ==Land and legal influence==