He served in the Bashi-Bazouk army in Darfur with the rank of "Buluk-bashi," meaning commander of twenty-five soldiers.

When Abu Anja was in the Jebel (Kordofan) region, he had previously joined the government in one of the regions of Darfur, collecting taxes. He then fled to the Mahdi, where he met Abdullahi al-Ta'aishi and became one of his supporters. He was appointed commander of the Mahdi's forces and became one of Abdullahi al-Ta'aishi's most prominent supporters. He then opened (Gonder), one of the large Abyssinian cities.

In any case, Abu Anja possessed noble character and excellent qualities. He was known for his intelligence and how he managed to win the hearts of men with kindness and leniency. One of the most touching stories I heard about his wisdom was when the Mahdi gifted Abu Anja a beautiful slave girl whose father was a king. Her family was displeased, saying, "If she sets foot in our land, she will be under the rule of a slave." When this news reached Abu Anja, although he was capable of punishing them, he did not. Instead, he summoned the girl's mother, gave her a thousand riyals, slave girls, and clothes. He did the same for the rest of her relatives. Then, he sent someone to gather information about them. The girl's mother was told, "Your daughter is a slave." She replied, "By God, she is above free people." The same was said to her father, who replied, "What has happened has happened, and the young man has been misled." In summary, he appeased them with kindness and was rewarded with kindness.

We have included this anecdote to illustrate Abu Anja's shrewdness and that the success he achieved in all his endeavors was merely a result of his actions, such as this rare example.

Al-Ta'aishi expressed his desire to send Hamdan Abu Anja to the Jebel (Nuba) mountains around Kordofan to raid and bring back slaves and livestock. The Mahdi agreed to his request, and Hamdan Abu Anja traveled with fifteen thousand fighters.