I looked in Encyclopedia, but could not find when elections as we understand them began. But the citation below suggests that in the early days, candidates for Commons were chosen by the barons.

The barons' leader, Simon de Montfort, summoned representatives of towns to Parliament for the first time in 1265. The so-called Model Parliament of Edward I (1295) contained all the elements of a mature Parliament: bishops and abbots, peers, two knights from each shire, and two representatives from each town.



"Parliament, British," Microsoft(R) Encarta(R) 98 Encyclopedia. (c) 1993-1997 Microsoft Corporation. All rights reserved.