Charles had arranged the marriage of his second son, Andrew, with his cousin Joanna, the granddaughter of King Robert of Naples, in 1332. Robert died in 1343, bequeathing his kingdom to Joanna but excluding the claim of Andrew. In 1345, a group of noble Neapolitan conspirators murdered Andrew at Aversa. Almost immediately, Louis declared war on Naples, conducting a first campaign in 1347–1348 and a second in 1350. He eventually signed peace with Joanna in 1352. Louis also waged wars against the Serbian Empire and the Golden Horde, restoring the Hungarian monarchs' authority over territories along the frontiers which had been lost during the previous decades.