20 January] 1868) was an Imperial Russian military officer and politician who took part in, among others, the Napoleonic Wars and the fights against the November Uprising.
Lukash was the illegitimate son of Alexander Pavlovich Romanov, the future Emperor Alexander I of Russia and one of his lovers, Sophia Sergeievna Vsevolozhskaya (19 November 1775 – 4/11 October 1848), daughter of Sergei Alekseyevich Vsevolozhsky (1751–1822) and wife Yekaterina Andreyevna Zinovyeva (1751–1836), who married c. 1798 Prince Ivan Sergeyevich Meshchersky (11 December 1775 – 17 March 1851), by whom she had an issue.
As the commanding officer of the Lutsk Grenadier Regiment, he took part in the Battle of Warsaw (1831) where he was promoted lieutenant-general of the Russian Army.
In 1859, he became a member of Senate and continued in service of the Russian state in various parts of the empire, notably in the Caucasus.
He married firstly Princess Alexandra Lukanichna Guidianova (26 May 1804 – 23 February 1832/4), daughter of Prince Luka Stepanovich Guidianov and wife Maria Ilyinichna Isakova, and had four children: He married secondly Princess Alexandra Mikhailovna Schakhovskaya (21 November 1806 – 29 January 1864), daughter of Prince Mikhail Aleksandrovich Shakhovskoy and wife Countess Yelisavyeta Sergeyevna Golovina, and had one son: