To unlock the historical missions, you have to beat the game under any difficulty mode:
Wake (Evacuate the Admiral): Historical Mission 1
Midway (Battle of Midway): Historical Mission 2
Guadalcanal (Backs Against the Wall): Historical Mission 3
Gilbert Islands (Million Men): Historical Mission 4
Marianas (Revenge): Historical Mission 5
If you want to get bonus planes, you should follow these recommendations.
These airplanes can be unlocked if you complete the indicated mission under the Ace difficulty mode:
Coral Sea - Yak 3
Gilbert Islands - P-51A Mustang
Guadacanal - Tempest Mk. II
Iwo Jima - P215-01
Marinaras - P-61A Black Widow
Marshall Islands - Fw-190A-8
Midway - P-47D Thunderbolt
Philippines - P-80 Shooting Star
Wake Island - Sea Fire Mk.III
These airplanes can be unlocked if you complete the corresponding missions under any difficulty setting:
Coral Sea (Scratch One Flat Top): PBY-5 Catalina
Coral Sea (Torpedo Practice): SBD-2 Dauntless and A6M2-N Rufe
Gilbert Islands (Million Men): B6N1 Jill
Gilbert Islands (Recon): Ki-102A Randy
Guadalcanal (Strike): B-26B Marauder and Ki-61-1A Tony
Guadalcanal (Tokyo Express): H8K Emily
Iwo Jima (Kamikazes): B-25G Mitchell
Iwo Jima (Landing): F8F Bearcat
Iwo Jima (Raise the Flag): J7W Shinden
Marianas (Revenge): Ki-84-1A Frank
Marianas (Usurper): F6F-3 Hellcat
Marshall Islands (Rescue Pilots): TBD-1 Devastator and J7M2 Jack
Midway (Defend Midway): TBF-1 Avenger
Midway(Mikuma): P-38D Lightning
Pearl Harbor (Surprise Attack): A6M2 Zero and B5M1Kate
Philippines (Samar Sea): D4Y2 Judy
Philippines (Steal Prototype): Me262
Wake (Combat Air Patrol): F4F-3 Wildcat and F1M Pete
Wake (Evacuate Admiral: F4U-1 Corsair and D3A1 Val
Wake (Wake Up): G4M2 Betty