Pāṇini mentions a number of towns in the region including Aisukari, Taushayana and Rori, which have been identified with Hisar, Tohana and Rohri respectively.

The city name Dhanagarh was given by Dhana Nanda who was the King of Nanada empire and his territory was from Pataliputra to Beas river in the north.

Furthermore, the discovery of Ashokan pillars at Hisar and Fatehabad shows that this area remained a part of Mauryan empire.

The people of Agroha area assisted Chandra Gupta Maurya in the war against the Indo-Greek Kingdom.

[citation needed] After the fall of the Mauryas and Shungas, the Agras along with the Yaudheyas – the republican tribes of the region – asserted their independence.

The Agras settled in the region covering Barwala and Agroha, the capital headquarters, from where they issued coins.

[citation needed] According to Anant Sadashiv Altekar, the Yaudheys made a second bid for independence towards the end of the 2nd century AD when they succeeded in freeing their homeland and ousted the Kushans.

The area of Agroha passed under Ghurid rule after the defeat of Prithviraj Chauhan III in the Second Battle of Tarain (1192).

[citation needed] After the Battle of Tarain, Sultan Shihab-ud-din Muhammad Ghuri placed one of his generals in the Indian campaigns.

[6] The legend assigns the association of the mosque to the Mughal Emperor Humayun who in his flight after his defeat at the hands of Sher Shah Suri happened to pass through Fatehabad.

By 1760, the areas became the scene of a sort of triangular duel between the sturdy Sikhs of north-east, marauding Bhattis of north-west and the Muslim chiefs of the south.

In 1774, Maharaja Amar Singh of Patiala along with his famous minister Dewan Nanumal laid siege to the stronghold of Bighar near Fatehabad which fell shortly afterwards.

But after a treaty of Jind in 1781, Fatehabad and Sirsa were made over to the Bhattis and remaining territories were allowed to be retained by the Sikhs.

When George Thomas was driven out from here by the Sikh-Maratha Confederacy, a French officer, Lt. Bourquian, controlled these areas on behalf of Marathas.

Fatehabad came into existence as a full-fledged district with effect from 15 July 1997, now having three sub-divisions, three tahsils and three sub-tahsils.

[9] The climate of the district is of tropical type with intensively hot summer and cool winter, with a temperature of 47 °C in June and 2 °C in December and January.

According to the 2011 census Fatehabad district has a population of 942,011,[11][12] roughly equal to the nation of Fiji[13] or the US state of Delaware.

At the time of the 2011 Census of India, 35.57% of the population spoke Hindi, 29.72% Punjabi, 20.81% Haryanvi and 11.56% Bagri as their first language.