By 1268 he had been "signed with the cross" for a pilgrimage to the Holy Land, in which year his father signed his will mentioning Walter as being a crusader to whom he bequeaths 200 marks "for his better performance of that voyage". He was at the Battle of Falkirk in 1298 and at the Siege of Caerlaverock Castle in Scotland in 1300, with the king. He signed and sealed the Barons' Letter of 1301 to the pope as Waltus de Bello Campo, Dns de Alcestre. Another of the signatories was his nephew Guy de Beauchamp, 10th Earl of Warwick.
At the Siege of Caerlaverock Castle in Scotland in 1300 the heralds blazoned the arms of all the English knights present in Norman-French verse, known as the Caerlaverock Roll. The part regarding "Wautier de Beauchamp" is as follows:
Which may be translated as:
Inherits Powick
At his father's death in 1269 Walter inherited his family's part of the manor of Powick in Worcestershire, where he made his seat at Beauchamp Court, on the right bank of the River Severn. The estate had been inherited, together with Elmley Castle and other lands, by Walter's three-times great-grandfather Walter I de Beauchamp, founder of the Beauchamp family, on his marriage to Emmeline d'Abitot, daughter and heiress of Urse d'Abitot, Sheriff of Worcestershire. In 1300 he received a royal grant of free warren in his demesne lands of Powick and at some time established a chantry "in the court of his manor" at Powick. The family he founded is generally referred to as "Beauchamp of Powick" to distinguish it from the other branches, namely the senior branch of Earls of Warwick "Beauchamp of Elmley" and another branch "Beauchamp of Holt". The martlet arms he adopted as a difference to his paternal arms were also borne by his descendants.
In about 1263 he acquired a moiety of the manor of Alcester in Warwickshire which he held from Reynold FitzPeter by the tenure of "doing the foreign service of ½ knight's fee". In about 1274 he confirmed to his free burgesses and tenants their ancient right to hold a weekly market on a Tuesday, and also granted them a weekly market on a Thursday, allowing the sale of animals, flesh, wheat, rye, barley, oats, beans, pease, woollen and linen drapery, bread, iron goods, tallow, grease, fish, leather goods, baskets, hides, wool, linen, geese, hens, cheese, bacon, eggs, salt and spices. In 1291 he received royal licence to cultivate 60 acres of his wood in Alcester within the forest of Feckenham and in 1300 he was granted by the king free warren in his demesne lands of Alcester. In 1292 he obtained a royal grant for an annual fair "on the eve, day and morrow of St. Giles and for five days following". The other moiety of the manor was eventually acquired in 1444 by his descendant John Beauchamp, 1st Baron Beauchamp "of Powick" in Worcestershire.
Walter de Beauchamp, of Alcester, eldest son and heir. In 1307 he was fighting the Scots and in 1317 he became the guardian of Warwick Castle and its lands following the death of his nephew Guy de Beauchamp, 10th Earl of Warwick who left an infant son Thomas de Beauchamp, 11th Earl of Warwick.
William de Beauchamp, "a military man of celebrity" who inherited some of his elder brother's lands. In 1320 he was appointed by King Edward II as Governor of St Briavel's Castle in the Forest of Dean, Gloucestershire. He married a certain Joan with whom in 1334 he settled the manors of Powick and Bransford on themselves and their heirs, but he died childless.
Giles de Beauchamp, heir of his eldest brother, who in 1340 received royal licence to crenellate his manor house at Alcester, and a similar licence two years later for his house at Freshwater, Isle of Wight. He married Katherine de Bures. His son and heir was Sir John de Beauchamp, who in 1386 was keeper of Gloucester Castle. Giles's great-grandson was John Beauchamp, 1st Baron Beauchamp "of Powick" in Worcestershire.