Unix timestamp before 1970 (even before 1700), using PHP

Question

how can i work with dates before 01.01.1970?

i need to get first day of the month for dates from year 1700.

how can i achieve that?

thank you in advance!

Answer 1

You can use DateTime.

Example:

<?php
$d = new DateTime("1780-06-01");
echo $d->format("l"); //Thursday

You should, however, consider that the Gregorian Calendar was adopted in different instants throughout the world.