The Grand Duchy of Mecklenburg-Strelitz was a territory in Northern Germany, held by the younger line of the House of Mecklenburg residing in Neustrelitz.

It consisted of two detached parts of the Mecklenburg region: the larger Lordship of Stargard with the residence of Neustrelitz to the southeast of the Grand Duchy of Mecklenburg-Schwerin and the Principality of Ratzeburg on the west.

[1] During the Napoleonic Wars it was spared the infliction of a French occupation through the good offices of King Maximilian I Joseph of Bavaria and his minister Maximilian von Montgelas; Duke Charles II declared neutrality in 1806 and joined the Confederation of the Rhine in 1808, however, he withdrew in 1813 on the eve of the German campaign in favor of an alliance against Napoleon.

He joined the German Confederation established by the 1815 Congress of Vienna to succeed the dissolved Holy Roman Empire; he and his cousin Frederick Francis I of Mecklenburg-Schwerin both assumed the title of grand duke (Großherzog von Mecklenburg).

The Congress of Vienna further recognized that the grand duke and four other princes should receive special compensation totaling 69,000 "souls" in the Saar region.

Mocked by Chancellor Otto von Bismarck as a safe haven in the face of threatening apocalypse "as everything there happens 50 years later", the grand duchy had always been a government of feudal character.

It met for a short session each year, and at other times was represented by a committee consisting of the proprietors of knights' estates (Rittergüter), known as the Ritterschaft, and of the Landschaft, which was composed of burgomasters of selected towns.

On 23 February 1918, Grand Duke Adolf Frederick VI committed suicide, leaving his cousin Charles Michael as heir to the Strelitz throne.

Being in Russia, however, Charles Michael did not assume the throne, and in 1918 he wrote to Grand Duke Frederick Francis IV of Mecklenburg-Schwerin, who was acting as regent in Strelitz, stating that he wished to renounce his rights of succession to Strelitz, though the letter was only received by Frederick Francis in 1919 after the end of the German monarchies, so the issue of succession could not be resolved at the time.