I study military history, and have for about 65 years.
It is such a wide subject that I specialize in 1920-1945. I have 200 or more volumes, hardback and paperback combined.
May I suggest looking in thrift stores for encyclopedias? I scored a 22 volume 1972 set of World Book for $15. The internet and google drove them into obscurity, but a set of encyclopedias was in most homes in the 1950's and 60's when I was growing up. It's fun to grab a volume at random and start reading for 30 minutes or an hour in the evening. (We don't watch TV at our house, it rots the brain)
It is such a wide subject that I specialize in 1920-1945. I have 200 or more volumes, hardback and paperback combined.
May I suggest looking in thrift stores for encyclopedias? I scored a 22 volume 1972 set of World Book for $15. The internet and google drove them into obscurity, but a set of encyclopedias was in most homes in the 1950's and 60's when I was growing up. It's fun to grab a volume at random and start reading for 30 minutes or an hour in the evening. (We don't watch TV at our house, it rots the brain)