Born in Umballa, India, Roberts attended Sandroyd School[2] before heading to Eton College and joined the British Army soon after completing his studies.

In 1898 he took part in the Nile Expedition following which he was promoted lieutenant, and awarded Order of Meijidieh, 4th class, from the Ottoman Empire.

[4] At the age of 27, Roberts went with the King's Rifles to the Second Boer War, when the following deed took place for which he was awarded the Victoria Cross.

Some of the horses and drivers were sheltering in a donga, a dried watercourse, about 500 yards behind the guns and the intervening space was swept with shell and rifle fire.

The Queen has been graciously pleased to signify Her intention to confer the decoration of the Victoria Cross on the undermentioned Officers and Non-Commissioned Officer, whose claims have been submitted for Her Majesty's approval, for their conspicuous bravery at the battle of Colenso, as stated against their names:— [...] The Rifle Brigade (The Prince Consort's Own) Captain W. N. Congreve At Colenso on the 15th December, 1899, the detachments serving the guns of the 14th and 66th Batteries, Royal Field Artillery, had all been either killed, wounded, or driven from their guns by Infantry fire at close range, and the guns were deserted.