Isaac Aaron was born in Birmingham, son of Abraham and Ann Aaron. He was Christened on 25 December 1805 at St. Philip's Birmingham.
He was educated at local schools and at St Bartholomew's Hospital where he qualified as a licentiate of the Society of Apothecaries in 1826 and as a member of the Royal College of Surgeons a year later 
He returned to Birmingham and in 1830 was practising his profession in Bradford Street, Deritend Birmingham.  In 1832 he was a Member of the Provincial Medical and Surgical Association and Surgeon to the Birmingham and Deritend General Self-supporting Dispensary. . In Pigot's 1837 Directory his address was 256 High Street Deritend.
Isaac Aaron was active in political reform and attended the Grand Radical Demonstration at Birmingham on Monday 6th August 1838. This was described as one of the most splendid and enthusiastic demonstrations in favour of Radical principles ever witnessed in the country.
Birmingham had given determined support to the passing of the Reform Bill. Early in the morning of the 6th parties were observed thronging to the town in all directions, accompanied with bands of music and other insignia. At ten o'clock the members of the political union were admitted to the Town Hall, a spacious and splendid building, for the purpose of receiving the delegates who came from different parts of the country and for the purpose of electing a council to transact the affairs of the union for the ensuing year. In a short time all the galleries and the body of the Hall were completely filled and several appropriate flags were suspended from different parts of the room. Isaac Aaron was elected member of Council of the Birmingham Political Union at this meeting. 
Just a few months later he set sail for Australia. He arrived with his wife Martha and two children on the barque Hashemy on 25th January 1839.
By June 1839 he was residing in Raymond Terrace. Martha gave birth to a daughter there on the 2nd of June 1839. He commenced his medical practice in Raymond Terrace and was listed as a qualified Medical Witness in this year. Martha died of cholera aged 37 in January 1840 and was buried in Christ Church burial grounds, Newcastle. His second marriage to Charlotte Mary Croker of Motto Farm took place at St. James Church, Sydney in November 1840.
In June 1841 Isaac Aaron moved from Raymond Terrace and advertised his 1/2 acre allotment in Port Stephens Street for sale. The property consisted of a substantial weather boarded cottage with four rooms, a detached kitchen, store, stable, bricked well, and a building used as a hospital. He moved to Sydney where he was employed as Surgeon to Darlinghurst gaol and resided at 4 Hyde Park Terrace, Liverpool Street, Sydney.
....Darlinghurst Gaol - Nation Art School
In 1870 Isaac Aaron was listed in the Blue Book. He was Surgeon in the Volunteer corps and Visiting Surgeon to the Gaol and Lunatic Reception House, Darlinghurst, Sydney.
Isaac Aaron died in 1877. The Sydney Morning Herald published his obituary: -
A man passed away from amongst us last week whose career is deserving of a brief notice. Mr. Isaac Aaron, who for the last eleven years filled the office of surgeon at Darlinghurst gaol, was a man who in his day took a worthy part in same of the historical struggles of English liberalism. In the years of the great struggle which agitated England from sea to sea, in 1830, 1831 and 1832 for the Reform Bill of Lord Grey, Mr. Aaron was a member of the council of the Birmingham Political Union, in company with Thomas Attwood, George Frederick Muntz, Joshua Scholefield, and George Edmunds, men a great political influence at the time. He was one of the speakers at the great reform gathering at Newhall Hill, when not less than 200,000 men assembled, and the story of which is so graphically told in Harriet Martineau's History of the Thirty Years Peace. The vast movement set on foot by the Political Union undoubtedly carried the Reform Act, and all through its existence the late Mr. Aaron was one of its most active leaders. At a later period, during the agitation for the abolition of Church rates, Mr. Aaron was one of those who, on the ground of principle, refused to pay the rates; and on one occasion 5000 or 6000 people assembled in the street before his house, when his chairs and tables, which had been seized for Church rates, were offered for sale, and nobody in that large crowd was found unpatriotic enough or bold enough to bid for them.
Mr. Aaron emigrated to NSW in 1838 and he brought a considerable sum of money to the colony; but we believe he embarked in some speculations soon after his arrival by which he lost very heavily. He never took a very prominent part in public affairs here, though in the year 1848 he actively exerted himself in securing the election of Mr. Lowe for Sydney and he took part in the movement for the abolition of transportation. Mr. Aaron combined with a sound knowledge of his profession a varied stock of political and general information, and he was one of the men who could always give a reason for his political belief. He was a bold and energetic speaker and a man of high spirit, whose usefulness was to some extent impaired by personal haughtiness and an ill concealed scorn for many who assumed to be his superiors. Such as he was, the community could ill afford to lose him.