Clone Commander Bly, or CC-5052 was a republic clone bred for war at Kamino. He was deployed in the galaxy when the war between the Republic and CIS began.
When General Grievous attacked Rishi Moon in order to gain acces to Kamino, Bly's forces tried to stop them. After a heavy battle, Bly and the remaining forces were trapped, after losing their naval forces in space. Reinforcements came sometime later, nearly succeeding in recapturing the base completely. However, intervention from general Grievous stopped this, and Bly was captured.
During his imprisonment, Grievous made Bly symphatise with the CIS cause. Bly joined the CIS, but actually had his own agenda, namely freeing clones and making them independent. He did several missions for the CIS, including PR speeches. On the first one he did, prime minister Bec-Lawise was shot.
He was replaced by Voe Atell, with which Bly had a less then ideal relationship. Nonetheless, he ordered his lieutenant (later referred to as "Boss") to see that nothing happened to her. Bly continued to distrust politicians, as he planned a breakout at Kamino. After a long time, it was prepared. He had built up tension with the CIS leaders however, and as he executed his plan, Grievous stabbed him, killing him nearly instantly.
Bly's legacy was passed on to Boss, and Bly's actions inspired many. Bly was even respected by Grievous, and that led to Grievous keeping Bly's body as a trophy at his lair.