Member Robyn Johnstone Nicols of New Zealand in her profile asked how the name Johnstone came to adorn the wee toun. An apt query, we thought.

Johnstone Castle in Renfrewshire takes its name from the Houston family’s baronial title “of Johnstone,” not from a founder named Johnstone. When the Houstons made the former Easter Cochrane tower their principal seat, they transferred their existing territorial name to it, creating “Johnstone Castle.”

Origins of the Johnstone title

- An older “house and lands of Johnston” lay across the Black Cart Water, long held by a Wallace family branch before passing to the Houstons in the later 17th century, giving them the territorial style “Houston of Johnstone.”[1]
- In 1733 George Houston sold this original Johnstone estate to Major James Milliken (who replaced it with Milliken House), but the Houstons retained the Johnstone designation even after disposing of the older property.[1]

Name applied to the castle

- The nearby tower house at Easter Cochrane (with earlier Cochrane-related names) was later acquired and developed by the Houston family as their main residence.[2][1]
- Because they already bore the baronial name “of Johnstone,” they re‑named this seat “Johnstone Castle,” so the castle’s name reflects the Houstons’ territorial title rather than the surname of the original tower builders.[2][1]

Sources