What do these numbers refer to? give situations 1835 1856 1842 1850 1861 1857 1865 1858 помгите

One thousand eight hundred thirty five-1835
one thousand eight hundred fifty six-1856
thousand eight hundred fifty-1850
one thousand eight hundred forty two-1842
one thousand eight hundred fifty seven-1857
one thousand eight hundred fifty eight-1858
one thousand eight hundred sixty one-1861
Удачи:)
one thousand eight hundred sixty five-1865