Italy locked down - 10th March (631 deaths, 1st death Feb 21st)
France locked down - 17th March (175 deaths, 1st death Feb 15th)
Spain locked down - 14th March (196 deaths, 1st death March 3rd)
Germany social distancing (not locked down) - 22nd March (94 deaths, 1st death March 9th)
UK started encouraging hygiene measures early March (0 deaths, 1st death March 5th), advised social distancing 16th March (55 deaths) and continued lockdown measures that week. People look at the lockdown of 23rd March as the date, but it began a week earlier, similar to the amazing Germany in that regard.
Info from here:
https://www.worldometers.info/coronavirus/