[Westminster Abbey, England, founded 1245]
England (b. c. 1240) - Kyrie. Rex Virginum Amator (c. 1270)
The two-voice trope Rex virginum amator, thought to be of British origin, is an example of relatively "late" early polyphony where a second voice is composed above the existing plainchant melody. Using our old friend Kyrie IV for the interpolated (troped) text, only the "eleyson" is heard at the end of each phrase.
[8240 Pipe and Tabor / 8240 Kyrie Trope / 8240 Pipe and Tabor]