Jeremiah Youngblood was a Phoenix Hawk LAM pilot who, by 3016, commanded the long-range scout lance of 3rd company, 2nd bataillon of the Kell Hounds. This notable lance consisted of his Phoenix Hawk LAM, two Stinger LAMs and a Wasp LAM.
While a member of the Kell Hounds, Youngblood took part in the fighting on Mallory's World. He left the unit when Morgan Kell reduced the Kell Hounds from a regiment to to a single bataillon following the Phantom 'Mech incident on Mallory's World in 3016.
Afterwards, Jeremiah Youngblood became a member of the original Crescent Hawks ("Katrina Steiner's personal lance") and commanded the small unit by 3028, although it is unknown when he assumed this command or when the Crescent Hawks were created. It is also noted that, after leaving the Kell Hounds, he spent most of his time from 3016 to 3028 looking for a lost Star League cache bunker on the world of Pacifica (Chara III) while his son Jason Youngblood was enrolled as a cadet at the Pacifica Training School.
Enroute to her daughter's wedding, Katrina Steiner paid a brief visit to Pacifica in 3028, and Jeremiah Youngblood served as Security Chief (Captain of the Security Forces) during her stay on the planet. Just at this time House Kurita staged a surprise attack against Pacifica. Jeremiah Youngblood went missing when the Citadel was destroyed and was presumed dead.
His son Jason and Crescent Hawks member Rex Pearce subsequently formed a guerrilla force and managed to thwart the Kurita invasion. Following hints left behind by Jeremiah, they found and gained access to the long-lost Star League cache that Jeremiah had found just prior to the invasion. His PHX-HK2 Phoenix Hawk LAM was parked within the bunker.
Jason and Rex already mused that Jeremiah Youngblood, being an ex-Kell Hounds member who had fought against Kurita on Mallory's World, might have been taken captive as House Kurita pursued a vendetta against the Kell Hounds ever since.
It later turned out that Jeremiah Youngblood had indeed been taken prisoner and was held captive on the Kurita district capitol of Dieron. Under the leadership of his son Jason and with aid from the Kell Hounds and the Federated Suns, the Crescent Hawks staged "Operation Liberty", an objective raid against the Dieron prison, in the middle of the Fourth Succession War and freed the prisoners, including Jeremiah Youngblood.
At the successful conclusion of Operation Liberty and the return of the DropShip in June 3029, Katrina Steiner promoted Jason Youngblood to Captain and made him commander of the Crescent Hawks. Nothing is said about the future of Jeremiah Youngblood, who had spent several months in Kurita captivity.
Besides his position as a LAM pilot with the Kell Hounds as of 3016, all information about Jeremiah Youngblood comes from computer games which are not considered valid sources of Canon; however both his son Jason and the Crescent Hawks have been confirmed as canonical in full-canon sources, as was the general backstory of both computer games. The story of Jeremiah Youngblood, as told throughout these games, is therefore ambigous canon.