A rich and varied history on a much underutilized and underappreciated humanoid, IMHO. There is ample information on the hobgoblin culture itself, as well on the individual hobgoblin NPCs. Each NPC has stats, tactics, suggestions on campaign use, history, and additional level progressions stats for medium and high-level campaigns. RDP also leaves little notes blocks in each section for you to write in your campaign-specific details and the NPC's history in your world. There are 6 very different NPCs with varying levels of detail. The Hobgoblin mercenary commander is especially detailed with 4 pages of history and an appendix exclusively devoted to his mercenary legion. With stats for the different troop types and leaders under his command, as well as tactics, organization, and units of note, he is bound to be a major player in your campaign.
[5 of 5 Stars!]