Not sure where else to put this as it covers every part of WW2
Antony Beevor - Author of The Second World War
I have now read two of his books and each one astonishes me. If you really want a concise encountment of what happened then there's no better place to start.
Yes, there are other reads and books that cover all of his subjects i.e. Spain, Crete, Normandy but non too many that are this accurate.
Trust me it's worth a read.