There are no recorded events this year. See an overview of when world history happened.
The year 3870 BC was a common year starting on a Thursday, just like 3967 BC, 3956 BC, 3950 BC, 3939 BC, 3928 BC, 3922 BC, 3911 BC, 3900 BC, 3894 BC, 3883 BC in the century before it and 3866 BC, 3855 BC, 3844 BC, 3838 BC, 3827 BC, 3816 BC, 3810 BC, 3799 BC, 3788 BC, 3782 BC in the next.
The coloured days highlight
births
,
deaths
,
political
,
scientific
,
artistic
and
other
historical milestones, and recurring events such as anniversaries and
holidays
.
The new
,
waxing
,
full
and
waning
icons indicate the phases of the moon and appear only for dates in the Gregorian calendar, i.e. after 14 October 1582. The Chinese calendar is available only from 1645 to 2644, the first millenium since the last reform. The coloured columns mark the Sundays, the last day of the week per standard ISO-8601.
The normal calendar page for the current /year?2013 contains an introduction to the intriguing history of the year as we know it. The Calendar Converter has more detail. The so called Perpetual Calendar uses a trick from before the age of computers to find the weekday for any Gregorian date. Also see an overview of all historical events in the last six thousand years.