He wrote an important first-hand account of the siege of Asirgarh Fort, where around 1,200 defenders held out against constant bombardment from British forces for weeks.

He quickly manoeuvred himself into being on good terms with Governor Richard Bourke and was soon posted to the penal colony of Norfolk Island as captain of the guard.

He arrived at Norfolk Island in March 1833 which was then under the command of Colonel James Thomas Morisset, a depressed man with a disfigured face and a reputation for brutal discipline.

The harsh treatment of the convicts under Morisset's reign coincided with a turbulent period on the island with several violent episodes and prisoner mutinies occurring.

[2][4] Morisset's mental and physical health declined and on 7 January 1834, he gave full authority to Fyans to act as Commandant on the island.

Around 150 prisoners initially overwhelmed guards stationed at the convict hospital and elsewhere, but Fyans quickly organised his soldiers to counter the outbreak, allowing them to fire freely upon the rebels.

Fyans ordered special sturdier cat o'nine tails to be used to flog the prisoners and heavier leg-irons with roughened surfaces were manacled to them.

Fyans kept the rebels locked-up, naked in overcrowded jails for many months in irons, inflicting mass floggings with thousands of lashes being meted out.

[5] After the mutiny, Morisset officially resigned and Governor Bourke offered the commandant position at Norfolk Island to Fyans on a permanent basis.

[2][3] After returning from Norfolk Island, Fyans again used his friendly relationship with Governor Bourke to obtain the position of commandant of the Moreton Bay convict settlement in 1835.

Graham's knowledge and ability to communicate with the Aborigines proved extremely useful to Fyans when in 1836 it was discovered that a group of survivors from the wreck of the Stirling Castle were living rough with the local clans to the north.

His patron, Governor Bourke, gave Fyans the civilian post of police magistrate at the newly colonised Corio Bay area near Melbourne in September 1837, settler pastoralists in the region having requested the colonial government for protection against Aboriginal raids.

[2] Guided by William Buckley, an ex-convict who had lived with the local Barrabool people for thirty years, Fyans arrived at Corio Bay in October and attempted to locate a suitable site for his police huts.

The Derwent Company of Charles Swanston had already laid claim to much of the region and Frederick Taylor, the manager of this giant sheep station, ordered Fyans to move on.

They travelled through stony and swampy country which was occupied by a large number of Aboriginal people who caught fish and eels through the use of a system of weirs.

[2] Arriving at Portland Bay, Fyans found that "no doubt numerous bad and improper acts have been committed" and recommended the establishment of a police station in the region.

With the support of sixteen Border Police troopers, his duties included making government returns for the licensed runs and their occupants, receiving their annual £10 licence fee and maintaining law and order between the squatters and the Aboriginal people.

Described as “a man of hasty temper and a high hand”, Fyans' word as commissioner was law in the district, his decisions often at odds with the interests of high-profile squatters .

Codd's death resulted in the colonial authorities taking formal action with Fyans and his troopers sent in to capture the ringleaders of Aboriginal resistance.

[2] In late 1841, two of Fyans' Border Police troopers were severely wounded in a skirmish with Aboriginal fighters at James Hunter's Eumeralla property.

Fyans returned to Eumeralla with a larger force in early 1842, capturing two leaders and killing two other prominent Aboriginal men during a battle with thirty warriors.

Smythe returned to Geelong and reported the case to Fyans, who organised a well-armed militia of ten Barrabool men to be sent to the Otways to deal with the Gadubanud.

Fyans and Smythe led the group into the region, where the Barrabool troopers killed all the known members of the Otway tribe, male and female, except for one girl who was taken back to Geelong.