A great number of these were produced during the WWII era with different dates listed on the back of the tuck. These decks were given to soldiers in the field to pass the time and ease the mind.  

A pinochle deck consists of two copies of each of the 9, 10, jack, queen, king, and ace cards of all four suits, for 48 cards per deck. Aces are always considered high. Pinochle follows a nonstandard card ordering. The complete ordering from highest to lowest is A, 10, K, Q, J, 9.