They leased and revived the Cymmer (lower Rhondda Valley) bituminous coal pits in 1844 and developed their coastal and international markets together.

He was also the inaugural president of the Cardiff Chamber of Commerce and he and his company made significant contributions to public causes including education and health.

During Insole's early childhood his father was a carpenter in Worcester and the family was associated with the Angel Street Independent (Congregational) Meeting House.

In 1828 the family moved to Cardiff where Insole's father began building his South Wales coal mining and shipping business.

They then leased and revived bituminous coal pits at Cymmer (Lower Rhondda Valley) in 1844, and in 1848 opened 36 coking ovens to supply the Taff Vale Railway Company.

[10][12] The Crimean War made 1855 a boom year for coal and Insole began intensive excavation of his Cymmer Old Pit.

[1]: 141 [16][10] The local communities were also devastated by the disaster as almost all the working-age men and boys perished and thirty-five widows and ninety-two children, as well as other dependent relatives, were suddenly left without any immediate means of support.

The evidence indicated that the explosion was due to defective mine ventilation and the use of naked flames underground, despite warnings from HM Inspector of Mines, Herbert Francis Mackworth, who stated that "the explosion arose from the persons in charge of the pit neglecting the commonest precautions for the safety of the men and the safe working of the colliery".

[10]: 153 Insole, described in The Cardiff and Merthyr Guardian as "the greatest sufferer in a pecuniary sense", contributed £500 (approximately equivalent to £59,000 in 2023) to the Relief Appeal Fund "in aid of the widows and orphans, and dependent relatives of the deceased" and undertook to meet the cost of the thirty graves opened at the Cymmer Chapel.

Following the death of his father in 1851 Insole moved his family two miles out of Cardiff to the healthier and increasingly fashionable city village of Llandaff.

In 1855 building started on Ely Court, a three-storey twin-gabled villa set in a large garden and approached by an imposing carriage drive.

[10][25][26] In the 1870s the house was extended and embellished in the neo-Gothic style that had been employed by William Burges to transform Cardiff Castle for Lord Bute.

[24] Three years later, he purchased the 7,291 acre Luxborough estate in Somerset, including the "picturesque and commodious shooting box",[26]: 118  Chargot House (or Lodge), numerous farms and cottages, and "thriving woods and plantations, together with a large tract of moor".

[34] He devoted over forty years to: improving his gardens and estates in different parts of the country, but more especially his unique residence and home at Ely Court.

Mr. Insole ... [took] an active part in the development of the [coal] trade, and by his knowledge and skill did much to assist in laying the foundation for the vast industry to which the success of Cardiff owes so much.

In 1890 he married Marian Louisa Carey (née Eagle), the widowed daughter of his former Dublin agent and sister-in-law of his eldest son who lived nearby in his Pencisely House mansion.

[4][60] Insole's profits were underpinned by the harsh and dangerous working conditions imposed on miners, and these caused the devastating effects of the 1856 Cymmer disaster.

However, after significant restoration, in 2017 the mansion was reopened to visitors for a wide range of community activities and events, and the gardens that Insole so loved are now a municipal park for public use.

[67][68][69]The following accounts include Insole's role in the development of the South Wales coal industry, although each is unreliable in various details, especially regarding his father's origins and early years as a merchant in Cardiff.