He was Marshal of Champagne, and joined the Crusade in 1199 during a tournament held by Count Thibaud of Champagne. Thibaud named him one of the ambassadors to Venice to procure ships for the voyage, and he helped elect Boniface of Montferrat as the new leader of the Crusade when Thibaud died.
Although he does not say so specifically in his own account, he probably supported diverting the Crusade first to Zara and then to Constantinople. While at Constantinople he also served as an ambassador to Isaac II Angelus, and was in the embassy that demanded Isaac appoint Alexius IV co-emperor.
In 1207 he began to write his chronicle of the Crusade, De la Conquête de Constantinople (On the Conquest of Constantinople). It was in French rather than Latin, making it one of the earliest works of French prose. Unfortunately, he leaves out information that may have portrayed the Crusaders negatively; for example, he does not mention why or when the Crusade was diverted. The historian Nicetas Choniates chronicles the same events from the Byzantine perspective, and is often read alongside Villehardouin's account.
Villehardouin's nephew (also named Geoffrey) went on to become Prince of Achaea in Morea (the medieval name for the Peloponnesus) in 1209. Villehardouin himself seems to have died shortly afterwards, perhaps in 1212.