Locke once was a thief of great renound. His skill was mainly in balancing and in entering his target's abode. His untimely end was met when he didn't quite make the leap over the top of a high building and a tower. He gives Dorian his amazing speed and acrobatic maneuvers.
Lleu was once a Druid who kept to herself. Her casting abilities made sure that the forrest that she inhabbited was kept safe. Her untimely end was met when she was stuck between a rock and a hard place. Or, in her case, a pack of wolves or an angry mob of villigers. She gives Dorian him her physical sight and some of his casting abilities.
Bois is probably the oldest spirit that Dorian has in his possesion. He owned his own monistary where he trained prospective students in the art of unarmed combat. Bois died during a revolt when his loyal students fought students that betrayed his teachings. Bois protects Dorian when he casts healing spells, and gives him advice on the old religions.
Gwendal was the strongest man in his village. When his sister fell ill, he took up the sword to gain money for her operation. He was known for cutting down even the hardiest foes in one mighty slash of his gigantic sword. Gwendal died in a battle just before he was allowed to see his sister for the first time in a long time when she wasn't sick. Gwendal gives Dorian his skill in arms and his strength during times of duress.
Linde was a beautiful cleric from far away lands. She was wise and powerful when it came to healing spells. She had a long line of suitors, each one was richer than the next. She met a painful end when one of them decided that if he can't have her, then no one will. Linde gives Dorian his healing spells.