Terminal color history

The original VT100 did support color if it had a graphics expansion card installed -- this configuration was known as the VT125. It was kind of strange because it had two output buffers (one for text and one for graphics) and two DACs: a grayscale one for the built-in display and a color one for an external display.

the later DEC graphics terminals supported color as well, but not through the escape codes which are used to color text today. I don't think any DEC terminal supported 256 simultaneous colors, though maybe the VT340+ did (exactly what the "+" stands for is unclear to me, but at least one old post claimed it was for a larger palette).

I don't know the history for non-DEC terminals very well, but at least the early vector terminals didn't support color and as you can imagine that would be quite a challenge so I'm not sure any of them ever did.