12th century

The 12th century was defined by the calendar of Earth as occurring from the year 1101 through the year 1200.

Events

 * The Second and Third Crusades are fought on Earth (1147-48 and 1189-92). In the latter war, King Richard the Lionheart fails to take Jerusalem.
 * The spheres are constructed by the Sphere-Builders.
 * Vissians were said (in 2153) to have developed warp capability "nearly a thousand years ago", placing it at some point after 1153.
 * The events surrounding Robin Hood take place in England.