well obviously Dr.Halsey is in charge of the SPARTAN-II program and James Ackerson is in charge of the SPARTAN-III, and dr.halsey is in charge of the SPARTAN-IV ( ackerson was suposed to be aswell but he died), but i am curiouse who was in charge of the SPARTAN-I program?
It is not Known
The Romans?
It is unknown who started it specifically, but what we do know is that it was an O.N.I. project.
The Spartan I program was originally called the Orion Project and only in later years was it called the Spartan I project. Halsey called her program Spartan II after the Orion Project had been commissioned and before Orion had been referenced as Spartan I. She felt those people were the first Spartans even though the program was not called that.
ONI was the department in charge, specifically ONI Section-III (the Special Projects section of ONI Beta-5 division). The Orions however were under the command of Naval Special Warfare command. A specific person running the program has not yet been revealed. Sergeant Major Johnson was an Orion. ONI talked of a disease called “Boren’s syndrome” that made people immune to the flood, though it was really a cover up for those who were Orions. This is why Johnson was not converted to a flood.
You can read much more on wiki, though how much of that is true you’ll have to read for yourself and check all of the references.
Here is that link:
Apologies that a direct answer to your question could not be given. This is just about the best info we have on the Orion Project. Considering it started much earlier in Halo-lore, we may never know, unless a prequel game comes out and the info revealed then. (Halo: Insurrection?) Anyway, it’s likely a team effort and credit not given to any one person, though that is just a guess at this point.