that was that

Verb

simple past tense of that's that

Japanese Meaning

「that was that」は、「that's that」の単純過去形です。つまり、この表現は、現在形の「that's that」の過去形であり、意味そのものというよりも活用形を示しています。

After the manager announced the layoffs, that was that, so everyone packed up and left.

マネージャーが解雇を発表すると、それで決着がついたので、みんなは荷物をまとめて出て行った。

Sense（1）

simple past tense of that's that

The pricker was used to level the fire half-way up the bank and that was that.