1264

1264 may refer to the integer 1264 or to the year 1264 CE. In mathematics, 1264 is an even composite number with prime factorization 2^4 × 79. Its proper divisors sum to 1216, making it a deficient number. In the Julian calendar, 1264 would have been a leap year, since it is divisible by 4.

As a year, 1264 is notable for events in the Second Barons’ War in England. On May 14, 1264, the Battle of Lewes saw the rebel barons led by Simon de Montfort defeat royal forces, and Henry III and his son Edward were captured. This victory allowed Montfort to exercise de facto control over the realm for a period and to pursue reform measures associated with the baronial program. The conflict helped set the stage for the 1265 Parliament, an early assembly that expanded participation in governance and is often cited as a precursor to later representative institutions. The year occurred within a broader context of feudal and dynastic struggles across the British Isles.

Beyond England, 1264 sits in the broader mid-13th century landscape of medieval Europe, a period defined by feudal authority, territorial power struggles, and ongoing religious and political transformations. The single year is primarily remembered for its English political and military developments, which had lasting implications for the balance between monarchy and reformist forces in the kingdom.