Johnsons was founded in Edinburgh in 1846 by John Henry Johnson, an intellectual property lawyer who was instrumental in the formation of the Chartered Institute of Patent Attorneys (then known as the Institute of Patent Agents) and who became its first president in 1881. By 1866, J.H. Johnson had opened an office in Glasgow and also one in London - the latter apparently to provide his Scottish clients with a better service, following the establishment of the Patent Office in London in 1852.
The business was continued by various member of the Johnson family, in particular James Yate Johnson, his son Christopher Johnson and his grandson Edward Johnson, who ran the firm from offices at 10 Stafford Street, Edinburgh from at least as early as the 1930s. Over the years, the London branch evolved into J.Y. & G.W. Johnson, while the Scottish branch remained Johnsons. The two branches were reunited in 1990, under the J.Y. & G.W. Johnson name, upon Edward Johnson's retirement.
In 2004, J.Y. & G.W. Johnson merged with Bromhead & Co. to form Bromhead Johnson and in 2009 the firm re-established its Edinburgh office, under the historic Johnsons name. Moreover, the by kind permission of the Johnson family, Johnsons is again operating from the traditional Stafford Street address.