Prince Alexander Petrovich of Oldenburg, also known as Duke Alexander Konstantin Friedrich of Oldenburg, was a general, senator, and member of the royal family, known for his generosity and original charitable projects.

He was born in 1844 in St. Petersburg to Prince Peter of Oldenburg and Princess Therese of Nassau, and his great-grandfather was Paul I, which held special significance. Alexander received his education at home, as was customary for a member of the imperial family, and then entered the Law School. In 1870, he became the commander of the Preobrazhensky Life Guards Regiment.

In 1876, the prince led the Petrovskaya Brigade, and during the Russo-Turkish War of 1877-1878, he distinguished himself as a hero. In 1880, he became the general-adjutant of Alexander II, but after his assassination in 1881, he returned to military service. In 1895, Alexander was promoted to the rank of general of infantry and soon became a senator.

Prince Oldenburg is known for establishing the Imperial Institute of Experimental Medicine in 1890, where he served as the chief patron. He proposed to Emperor Alexander III to create a Russian equivalent of the Parisian Louis Pasteur station, and the Tsar agreed, but at the prince's expense. The institute focused on studying diseases and finding methods to combat them, although Ilya Mechnikov declined to become its director.

Additionally, Alexander Oldenburg supported the St. Petersburg Imperial Law School and other charitable institutions. In 1897, he became the chairman of the anti-plague commission and proposed to create a laboratory at Fort Alexander I, which became known as the Plague Fort. The prince financed the reconstruction of the fort and provided horses for research.

In 1903, Alexander Oldenburg founded the resort of Gagra, transforming it into a modern city with infrastructure, including a railway, electricity, and water supply. Schools, libraries, and other institutions emerged here, as well as a seaside park with exotic plants.

In 1914, with the onset of World War I, the prince became the supreme commander of the sanitary and evacuation unit, organizing medical assistance at the front and in the rear. His efforts were highly appreciated, and in 1916 he received awards from three emperors.

After the February Revolution of 1917, Alexander Oldenburg left Russia and settled in France, where he passed away in 1932. He was buried in Biarritz, on the Atlantic Ocean coast.