Grand Duke Nikolay Mikhailovich was born on April 14, 1859, in Tsarskoye Selo.
He was the first of seven children of Grand Duke Mikhail Nikolaevich and Grand Duchess Olga Fyodorovna.
In 1862, the family moved to Tiflis, as Nikolai Mikhailovich’s father was appointed the Tsar’s viceroy in the Caucasus.
In 1875, Nikolai Mikhailovich received his first officer’s rank.
During the Russian-Turkish War of 1877–1878, in October 1877, the prince was awarded the Order of St. George, 4th Class.
By the beginning of World War I, the Grand Duke had risen to the rank of General of the Infantry.
Nikolai Mikhailovich also played a significant role in the development of Russian lepidopterology (the science of butterflies).
He managed to assemble the largest collection of lepidoptera in Russia at the time, consisting of 110,220 specimens and comprising 13,904 species.
In 1900, the Grand Duke donated his entire collection to the Zoological Museum of the Academy of Sciences.
Nikolai Mikhailovich described 10 new butterfly taxa.
In recognition of his contributions, 18 insect taxa were named in his honor.