Reading an account of the adventures of Rodrigo Diaz de Vivar, popularly known as El Cid, I came across a delightful bit of history.
In the eleventh century the Iberian peninsula was a crazy free-for-all and among the players were the counts of Barcelona. At one point there were two counts who were joint rulers and also twins: Ramon Berenguer and Berenguer Ramon. These brothers were the son of Ramon Berenguer I (“the Old”). Anyway, Ramon Berenguer II (known as “the Towhead”) died in a hunting accident (oddly enough, William II of England died around the same time in similarly mysterious circumstances). Brother Berenguer Ramon II (known as “the Fratricide”) then took over. His nickname tells you something about the suspicions there were at the time over his involvement in his brother’s death.
That all this was going on between twins with reversed names just seemed like too much fun for me. As things worked out, the Fratricide Berenguer Ramon was later succeeded by his brother the Towhead’s son, who became Ramon Berenguer III (and who was also Ramon Berenguer I, Count of Provence). With these unimaginative names you can tell why they needed additional descriptive monikers. Ramon Berenguer III is known as the Great on account of his success in battle. On his death he left his Catalan possessions to his eldest son Ramon Berenguer IV and Provence to his younger son, Berenguer Ramon.