Geoffrey de Morton (died c. 1317) was a wealthy merchant and shipowner in early fourteenth-century Dublin who served as Mayor of Dublin in 1303.
He acquired a bad reputation for unscrupulous business methods and corruption: in particular, he was responsible for the murage scandal of 1308 to 1313, in which he misappropriated crucial public funds intended for the defence of the Dublin city walls.
According to Elrington Ball, Geoffrey de Morton came from a prominent Anglo-Norman family which had settled in Dublin, though little seems to be known of them. He made his fortune by trading with England, Scotland and France, in wine among other commodities. Presumably his wealth was the main reason he was chosen as Mayor of Dublin. He was plunged into controversy almost immediately after his election when he was accused of stealing the official seal of Dublin Corporation for his own private use. Geoffrey insisted that it was not he but his wife Maud who had stolen the seal, and the Corporation seems to have accepted this rather implausible explanation, although what motive his wife might have had for the theft of the seal was unclear. which had been damaged by fire. Geoffrey claimed to have employed stone masons to repair it, and that he himself had spent more than ã80 on the work. He neglected to mention that as he himself was the tenant of Isolde's tower, he was legally obliged to keep it in good repair at his own expense. The licence was granted and confirmed by an Act of the Irish Parliament, The verdict was that William must give an account of his profits.
They had two daughters: Maud, and Alice who married the High Court judge John de Grauntsete. Alice died c. 1335.