He was born in Tokat. His real name was Osman Nuri. His father’s name was Mehmed Efendi, who was an official at timber customs. His mother’s name was Şakire Hatun. He was an only child in the family. When he was seven years old, with his family he moved to İstanbul where his father lived. First, he was registered to Beşiktaş Military Junior High School. Then, in 1844, he was registered to Military Preparatory School where his uncle worked as a supervisor. Finishing his education in five years in Military Preparatory School, he entered the Military School and he graduated from the Military School in 1853 in the military rank as a lieutenant. However he was registered to General Staff, when the Crimean war broke out, he was sent to the Military forces in Rumelia. He got a rank promotion as a first lieutenant as he showed great capability and bravery on the 21st of March, 1855. After the end of the Crimean war, he continued The General Staff. After finishing the General Staff, he worked there for a while and a year later he became a captain. In 1859, when the government decided to conduct census and to draw a map with the method of land registry in Ottoman Country, and to start the action in the city Bursa, he was appointed to this mission as a military representative and continued it for two years. After he performed his duty in Rumelia Army in 1861, because of Yusuf Kerem rebellion, he was sent to Cebelilübnan and performed well there. In 1866, because of Greek Riot, he was sent to Crete. He became very famous for his efforts and self-devotion there. He specifically won Serdarıekrem Ömer Paşa’s appreciation and got a rank promotion as a full colonel and was awarded with a tertiary Mecidiye Medal. With his great success, he became a colonel when he was in Yemen. However, he moved to İstanbul in 1871 because he was unable to get used to the weather conditions in Yemen. After living in in İstanbul for a few months, he was appointed to Redif Force (Redif Livalığı-Sancaklığı) of the third Military Force and for a while he stayed in monastery which was the headquarter of the army. In 1873, he became the commander of Yenipazar Division and got a rank promotion as a major general. Later, Osman Paşa was appointed to İstanbul Commandery. After performing his mission for a short time there, first he was sent to İşkodra Commandery in Albania, and then to Bosnia Commandery. Because of the disagreement between Bosnia Governor Derviş Paşa and Osman Paşa, in 1875, although he was appointed to the Fourth Military Force of the General Staff which was in Erzurum, he was sent to Niş in the same year because of the chaos. After that he was appointed to Vidin Commadery. When Serbian Prince declared war against Ottoman State on the 1st of July, 1876, he defeated the Serbian Army which was in the command of Russian generals. These victories caused him to have his real reputation. He got a rank promotion as a Marshal with the second-order Mecideye medal.
When Russians declared war against Ottoman State on the 24th of April, 1872, Osman Paşa was commanding the West Military Forces in Vidin. As soon as he was issued an order, he set out from Vidin with 25,000 soldiers and arrived in Plevne on the 7th of July, 1877. On 8 July 1877 Gazi Osman Pasha opposed the attacks of the Russians under the command of General Schilder of German origin. This bloody clash that took place in history as the Battle of Pleven I. was the first coup that the Russians suffered in the Rumelian front in the 1877-1878 Ottoman-Russian wars. The Russian forces who got the reinforcement attacked Pleven on July 18 for the second time. However, in the twenty-six-hour war, the Russians were once again defeated by the resistance and the counterattack. Russians who helped the Romanians join the war, did not succeed in The III. battle of the Pleven which took place on 7-11 September. Upon this triumph, Osman Pasha was given the title of gazi. On the 13th of September, the Russians, who had failed to succeed one another, besieged Plevne. During this prolonged siege, ammunition and food shortages began to attract the fortresses who decided to move. On the morning of 10 December, Osman Pasha, who divided his army of 40.000 soldiers into two parts, was injured by a piece of shrapnel as a result of fire of Russian-Romanian gunners while trying to cross Vid water. He had to surrender to the general staff of the war, stating that there was nothing more to be done. For a while he lived in Bugot, Bucharest, Harkof and Russia the life of captivity. A double eagle prize was given by the Russian tsar for his heroism. For his return to Istanbul, Abdulhamid II sent head soldier Mushir Rauf Pasha to St. Petersburg, where he was honoured with great military assistant and ambassador. The arrival of the delegation of Osman Pasha in Istanbul (12-13 March 1878) was celebrated with a magnificent ceremony.
Osman Pasha was nominated to the consultant of Hassa Army in March 1878. On 5 November 1878, he became the servant of Prophet Mohammad, under the auspices of the Hassa august, and remained in this position until his death: even after his death no other appointments were made to replace him. Besides, he was accused of being a supporter of war upon the invasion of East Rumelia and dismissed from this duty. Osman Pasha, who was rewarded with first-rank insignia by foreign presidents and monarchs, who appreciated himself, including pope in addition to Mecidi and the concession insignia from the first rank, of mafharet, first rank, Edhem Pasha in 1897 Ottoman-Greek War, In the press on April 23, 1897, when the Greeks were told about the victory, they were sent to the battle place to carry out the movement.
In addition to his military personality, Gazi Osman Pasha had political activities during his duties in the palace. In the face of the pressure of the British on the Ottoman Empire, he ensured the unity of religious groups by having a firm place among the Muslim elements in Istanbul. He also contacted anti-British groups in India, Egypt and Arabia. He participated in the commission studies on the improvement of the army in the Yıldız Palace. He argued that the reform process should be free of European influence and dependent on values and opposed the decisions of the reform committee. The political struggle between him and the Grand Vizier Hayreddin Pasha resulted in the resignation of Hayreddin Pasha on 16 July 1879. His opposition to his opponents' ideas and tendencies led to a number of charges against him. To examine these allegations, the commission claims established by the sultan revealed that the allegations were unfounded. During his stay in the palace, he tried to influence Abülhamid on foreign policy issues. He died on Friday, 4-5 April 1900, and was buried next to the Tomb of Sultan Mehmed the Conqueror. Osman Pasha could speak Arabic, some Persian and French. He had four children named Nureddin, Kamâleddin, Cemâleddin and Hüseyin Abdulkadir from a marriage he had with Ferik Neşet Pasha's sister Zâtıgül Hanım. His descendants still live in Istanbul, Cairo and Paris. II.Abdulhamid had married his two daughters to two sons of Osman Pasha because he had appreciated him so much.
Reference: Türk Diyanet Vakfı İslam Ansiklopedisi cilt 13. İstanbul 1996. s.464-465 Mehmet Metin HÜLAGÜ