He served as the Governor-General of India from 1848-1856.
After the conquest of Punjab, Sindh and Avadh, the frontiers of the company were extended and the military interest of India was transferred to the North.
Thus Dalhousie shifted the headquarters of the Bengal Artillery from Calcutta to Meerut.
After some reduction in the strength of the Indian element the army stood at 2, 23,000 men in 1856, as against 45,000 Europeans.
As he had no confidence in the Indians, a new Gurkha regiment was created.
He was the father of Indian Railways.
The first railway line connecting Bombay with Thane was laid down in 1853.
The following year a railway line was constructed from Calcutta to Raniganj coal-fields.
In 1852 Dalhousie introduced the Electric Telegraph System in India.
The first telegraph line from Calcutta to Agra was opened in 1854, covering a distance of 800 miles.
By 1857, it was extended to Lahore and Peshawar.
In Burma a line was laid down from Rangoon to Mandalay.
A new post office act was passed in 1854.
Postage stamps were issued for the first time.
Before Lord Dalhousie, military boards were in charge of the construction of Public Works.
A separate Public Works Department was established by Lord Dalhousie.
The Chief Works of this department was to construct roads, bridges and government buildings.
Irrigational works were undertaken on an extensive scale.
The construction of Ganges Canal was completed and was inaugurated on April 8, 1854.
The construction of Grand Trunk Road was taken up.
Dalhousie’s special contribution was the construction of an engineering college at Roorkee and in other presidencies.
Dalhousie abolished female infanticide.
He also abolished the practice of human sacrifice practiced by the khonds of Orissa, Madras and Central Provinces.
Dalhousie passed the Religious Disability Act in 1850 which enabled the Hindu convert to inherit his ancestral property.
Moreover, he also passed the Widow Remarriage Act in 1855 which legalized the marriage of Hindu widows.
In 1856 Oudh was annexed on the pretext of misgovernment.
All ports of India were declared free.
The harbours of Karachi, Bombay and Calcutta were developed and light houses were also constructed.
In 1857 examining universities on the model of London University were established at Calcutta, Bombay and Madras.
These universities were to hold examinations and award degrees.
Vernacular Schools were opened in the villages and education was imparted to the children through vernacular or regional language of the province in the Lower Classes.
The Doctrine of Lapse was an annexation policy purportedly devised by Lord Dalhousie.
By applying the doctrine of lapse, Dalhousie annexed the States of Satara (1848 A.D.), Jaipur (1849 A.D.), Sambhalpur (1849 A.D.), Bahat (1850 A.D.), Udaipur (1852 A.D.), Jhansi (1853 A.D.), and Nagpur (1854 A.D.).
Annexation by lapse of ‘Karauli’ was disallowed by the Court of Directors.