Before his death, the old king had exiled Prince Edward's favourite Piers Gaveston, and Warwick was among those charged with preventing Gaveston's return.
The new king, however, not only recalled his favourite, but soon also gave him the title of earl of Cornwall.
Warwick was the only one of the leading earls who did not seal the charter, and from the start took on an antagonistic attitude to Edward II.
Gaveston was a relative upstart in the English aristocracy, and made himself unpopular among the established nobility by his arrogance and his undue influence on the king.
He gave mocking nicknames to the leading men of the realm, and called Warwick the "Black Dog of Arden".

Gaveston was once more forced into exile, but Edward recalled him in less than a year.
The king had spent the intervening time gathering support, and at the time, the only one to resist the return of Gaveston was Warwick.
With time, however, opposition to the king grew.
Another source of contention was Edward abandoning his father's Scottish campaigns, a policy that opened the Border region up to devastating raids from the Scots.
This affected Warwick greatly, with his extensive landed interest in the north.
Tensions grew to the point where the king in 1310 had to ban Warwick and others from arriving at parliament in arms.
They still did, and at the parliament of March 1310, the king was forced to accept the appointment of a commission to draft a set of ordinances towards reform the royal government.

The leaders of these so-called Lords Ordainers were Robert Winchelsey, Archbishop of Canterbury, on the side of the clergy, and Warwick, Lincoln and Lancaster among the earls.
Henry de Lacy, Earl of Lincoln, was the most experienced of the earls, and took on a modifying role in the group.
Thomas of Lancaster, who was Lincoln's son-in-law and heir, was the king's cousin and the wealthiest nobleman in the realm, but at this point he took a less active part in the reform movement.
Warwick is described by some sources as the leader of the Ordainers; he was certainly the most aggressive.
The set of Ordinances they drafted put heavy restrictions on the king's financial freedom, and his right to appoint his own ministers.
It also—once more—ordered Gaveston to be exiled, to return only at the risk of excommunication.
Before his death, the old king had exiled Prince Edward's favourite Piers Gaveston, and Warwick was among those charged with preventing Gaveston's return. The new king, however, not only recalled his favourite, but soon also gave him the title of earl of Cornwall. Warwick was the only one of the leading earls who did not seal the charter, and from the start took on an antagonistic attitude to Edward II. Gaveston was a relative upstart in the English aristocracy, and made himself unpopular among the established nobility by his arrogance and his undue influence on the king. He gave mocking nicknames to the leading men of the realm, and called Warwick the "Black Dog of Arden".
Gaveston was once more forced into exile, but Edward recalled him in less than a year. The king had spent the intervening time gathering support, and at the time, the only one to resist the return of Gaveston was Warwick. With time, however, opposition to the king grew. Another source of contention was Edward abandoning his father's Scottish campaigns, a policy that opened the Border region up to devastating raids from the Scots. This affected Warwick greatly, with his extensive landed interest in the north. Tensions grew to the point where the king in 1310 had to ban Warwick and others from arriving at parliament in arms. They still did, and at the parliament of March 1310, the king was forced to accept the appointment of a commission to draft a set of ordinances towards reform the royal government.
The leaders of these so-called Lords Ordainers were Robert Winchelsey, Archbishop of Canterbury, on the side of the clergy, and Warwick, Lincoln and Lancaster among the earls. Henry de Lacy, Earl of Lincoln, was the most experienced of the earls, and took on a modifying role in the group. Thomas of Lancaster, who was Lincoln's son-in-law and heir, was the king's cousin and the wealthiest nobleman in the realm, but at this point he took a less active part in the reform movement. Warwick is described by some sources as the leader of the Ordainers; he was certainly the most aggressive. The set of Ordinances they drafted put heavy restrictions on the king's financial freedom, and his right to appoint his own ministers. It also—once more—ordered Gaveston to be exiled, to return only at the risk of excommunication.
Guy de Beauchamp, 10th Earl of Warwick