Horseman will oversee the Arsenal U19 team for the UEFA Youth League and National Cup tournaments.
Arsenal's academy chief, Per Mertesacker, expressed enthusiasm about welcoming Horseman to the club, citing his extensive knowledge of the game and footballing experience.
Mertesacker highlighted Horseman's ability to bring his expertise to the club, benefiting both staff and players, and praised his fit with the club's culture.
Horseman is looking forward to contributing to the development of Arsenal's players and working with the UEFA Youth League and EFL Trophy teams.