Another difference between "was" and "had been" :

We use the past perfect (eg "had been") to indicate something that happened in the past before something else happened  OR something that happened in the past and was still going when another event occurred. 

e.g. I had been in Brussels only three hours when the explosions occurred.

But: I was in Brussels when the explosions occurred.

Hi, the different is :

WAS is the  simple past of the verb to be and is used in shares concluded in the past, for example : Yesterday there was a great film on TV.

HAD  is the perfect continuous and is formed with the auxiliary had and the past participle. It is used to talk about an action in the past, which took place before an 'always another action in the past :When we arrived at Sue's house, she had already left.

HAD BEEN is the pest perfect continous and is formed with the auxiliary had been and the -ing form of the principal verb. It is used to describe an ongoing action ended at some time in the past. I had been watching horror films, and my mind was full of strange images.