でした could be an inflection of です, with these forms:
- Ta-form. It indicates the past tense of the verb.
More reading
The word だ, and its polite form です, is similar to the English word “is”. Here are a few good articles to learn more.
- Tae Kim's Guide to Learning Japanese: Expressing state-of-being, Formal Expressions （である、ではない）
- IMABI: Copular Sentences I, Copular Sentences II, Copula Verb Variants
Sentences — 906 found
More Sentences >Names — 1 found
でした
【出下】
1. Deshita