He was christened on 16 Aug 1813 in Cambridgeshire. He served in the 1st Royal regiment Canada where he was convicted for desertion in 1838. He was transported as a convict to Van Diemen's Land from England in 1839.
John married Sarah Briggs in 1845 and was conditionally pardoned in 1849.

Sarah was born about 1828, probably in Yorkshire and arrived in Van Diemen's Land on the 'Medway' as an 11 yr old. Her father, Isaac Briggs, was already in Van Diemen's Land as a convict. Her mother, Alice, died between Sydney and Hobart Town in 1839.

John and Sarah went on to have eleven children.

John Cocker was born in September 1812 and baptised in Welney, Cambridgeshire (now Norfolk) in 1813 to parents John Cocker and Margaret unknown. John senior had a prior marriage in 1805 but his first wife died 6 months later. His sister Sarah was baptised in 1810. John junior was a witness at her wedding in 1830 to George Summers, she died in 1897 in England. Their father died in 1826 aged 40.

Private John Cocker (No.863) enlisted at Glasgow, Scotland 7th February 1832 with the 1st Royal Regiment of Foot. He deserted 17thJune 1832 at Glasgow and was recaptured 21st September 1833. He was court-martialled and sentenced to 2 months hard labour, being released from regimental cells on 14th November 1833. In March-June 1834 he had 6 days sick leave whilst in Dublin, Ireland.

In October he was on detachment at Shannon Bridge and was back with the main body of the regiment at Dublin by November. He took 6 days sick leave between October and 18th December 1834 whilst in Dublin and then he deserted again on 18th December 1834. He rejoined the regiment from civilian custody on 29th January 1835 whilst at Longford, Ireland.

John was sentenced to 6 weeks solitary confinement at a Court Martial held in Athlone, Ireland on 2nd February 1835 and was marked with the letter 'D'. From July-September he had a further 9 days sick leave, followed by 8 days in October- December. In January-March 1836 he was sick for 2 days however, marched with the regiment from Enniskillen to Dublin between 26th March and 2nd April 1836.

On 29th June he boarded the vessel from Dublin to Canada- the journey taking 53 days; however time may have been spent in port at Dublin or Montreal. The regiment arrived at Quebec in August 1836 and was based in Montreal but John was on detachment at St Helens in January 1838. In February 1838 John rejoined the regiment in Montreal but deserted again 14 July 1838 only to be recaptured 23rd July 1838. He was held in confinement and then tried by Court Martial at Montreal, Lower Canada, convicted of desertion from the Royal Regiment and sentenced on 15th August 1838.

Court Martial transcript
Private John Cocker 863, 2nd Battalion 1st (or the Royal) Regiment of Foot was arraigned and brought to trial on two charges:
(1) for deserting from the Regiment at Montreal on or about the night of 14th July 1838 and not returning until brought back by an escort on or about the evening of 23rd July 1838.
(2) for making away with or losing through neglect one side belt and bayonet complete, being part of his Regimental appointments.

To which the prisoner John Cocker pleads guilty. Three witnesses in evidence for the prosecution were heard.

Question by the court: 'Has the prisoner been warned that his former convictions would be brought in evidence against him?'
Answer: 'Yes he has.'
Question by the court: 'What is the age, length of service and general character of the prisoner?'
Answer: 'He is 25 years and 11 months of age; he has been 6 and a half years in the service and his general character is bad.'
The court is closed
The prisoner John Cocker being called on for his defence has nothing to urge in explanation

Opinion and finding of the Court Martial:
1st charge: guilty
2nd charge: guilty

The court having found the prisoner GUILTY of both the charges preferred against him which being in breach of the Articles of War and taking into consideration his former convictions and general bad character do now sentence him the prisoner Private John Cocker 863 2nd Battalion 1st (or the Royal) Regiment of Foot to be transported as a Felon for 21 years and further to be marked with the letter D after the manner prescribed by the Mutiny Act.
(signed) Arthur W. Biggs Major 7th Hussars and President
(signed) G. Muller Capt. The Royal Regiment (acting) Deputy Judge Advocate
Confirmed: His Excellency Sir John Colborne Lieutenant General Commander of the forces in the Canadas.

His name appears on a list of military prisoners in the Quebec city gaol awaiting transportation (our RG 8, series I, volume C 173, page 43) - which list offers less detail than that found in Home Office records. The month is thought to have been September or October. One point not clear in the record is whether he was sentence directly to transportation or had a death sentence commuted to transportation.

John was transferred on 30 November 1838 to the hulk 'Leviathan' moored at Portsmouth, England. He spent several months on the 'Leviathan' (entry # 4371), appearing on the quarterly returns for the last quarter of 1838 and the first quarter of 1839 (see Home Office 8,volumes 58 and 59, for Leviathan # 4371). This suggests he travelled by steam-boat from Montreal to Quebec, and was sent onward to England on 2 November 1838 aboard the HMS 'Atholl', arriving before the end of December - the records in HO 8 and HO 9 rarely note dates of arrival on the hulks.

His transfer to the transport the 'Marquis of Hastings' on 12 March 1839 is recorded both in the quarterly return HO 8/59 and in the register of 'Leviathan' (HO 9/14, folio 47). He departed England 12March 1839 on the 'Marquis of Hastings'. He was a shoemaker aged 25,single, illiterate and with a bad gaoler's report. Three months and 17,000 km later he arrived in Van Diemen's Land.

Extract from Tasmanian state library records
- signed by B Wray, State Librarian 'He arrived on board the Marquis of Hastings on 23rd July 1839 from Portsmouth, England, after having been sentenced to twenty one years for desertion, at a court martial in Canada on 14th August 1838. He stated the offence 'Desertion, absent four days' and also said that this was his third conviction for desertion.

Convict record
John's official convict records (2488) records described him as:

oTrade - Shoemaker
oHeight - 5ft 8 inches (172 cm)
oAge - 27 (DOB 1812)
oComplexion - Dark
oHair - Dark Brown
oWhiskers and Eyebrows - black
oHead - round
oEyes - blue
oNose, mouth and chin - medium (CON 31/8, 52/2 18/16)
They show his time was troubled.

15th June 1841
John was sentenced to twenty four lashes for disobedience of orders
18th November 1841
John was sentenced to 14 days solitary confinement for insolence
1st November 1842
John was sentenced to six months hard labour in chains for cruelly mistreating a horse and for insolence. At this time he was in the Ross chain gang. This was his third conviction since 1841 and his records note that he was 'never to be again assigned'
21st December 1842
29th December 1842
He was sentenced to seven days solitary confinement for refusing to work on the road gang
15th April 1843
He was given another four days solitary confinement for neglect of duties on the road gang
1st May 1843
Another charge of neglect of duty saw him sentenced to 24 hours solitary confinement
4th October 1845
A charge of misconduct resulted in a sentence of 3 days solitary confinement

On 27th July 1845 he applied to marry Sarah Briggs and this application was approved. Marriage records show that John Cocker aged33 years, shoemaker married Sarah Briggs aged 17, spinster at the Church of England at Green Ponds (now Kempton) on 22nd August 1845.John and Sarah went on to have eleven children: seven sons and four daughters

John was given a ticket of leave on 10th February 1846 and was granted a Conditional Pardon on 30th January 1849.

John died in 1872 when accidentally killed by falling into the drum of a steam threshing machine. His grave is in the grounds of the Evandale Uniting Church and a plaque and seat in his memory have been placed there by his great-great-granddaughter Julie Blackberry.