The first successful attempt to organise workers in the clothing industry was the formation of the Witwatersrand Tailors Association in 1918. This period in the history of the union is characterised by its attempts to stamp out 'sweated labour' and the systems of contracting and piecework, and to improve working conditions. The union was divided into two sections, the bespoke and the factory. An attempt was also made to ensure that employers and manufacturers adhered to log prices and did not underpay workers in order to be competitive.

After the strike of 1922, the government introduced machinery to regulate relations between workers and employers. This was the beginning of an attempt at conciliation which was later much championed by the leaders of the Garment Workers Union. The Industrial Conciliation Act was passed in 1924 and the Garment Workers Union was one of the first to be registered. With the formation of the Industrial Council for the Bespoke Tailoring Industry in 1928 and then the Industrial Council for the Clothing Industry, the union became party to both councils

The union's membership was not confined to the Witwatersrand, but was extended to Bloemfontein where a branch was established by the Secretary, Cecil Frank Glass, in 1926. The members were mostly older males, many of them Jewish tailors who had emigrated from Eastern Europe to South Africa. During this period there were a number of individual strikes by workers against their 'rat employers'.

The Witwatersrand Tailors Association was active in promoting a trade union federation in South Africa, supporting first the South African Industrial Federation, and then, during its decline in 1922, the formation of ATUSA (Associated Trade Unions of South Africa) which later became SATUC (South African Trade Union Congress). The active leaders included M Baum, D Colraine, C F Glass, H Joseph and A F Tuffin.

The election of Emil Solomon 'Solly' Sachs as General Secretary on 14 November 1928 heralded a new era for the union. Sachs and his thinking dominated all its activities until 1952. He came to South Africa from Latvia at the end of 1913 or the beginning of 1914 (Sachs gives conflicting dates in various biographical accounts). He attended school until 1916, then worked in a bookshop and later in mine shops on the Witwatersrand. In 1919 he was active in the Reef Shop Assistants Union which agitated for shorter hours. According to Sachs' own testimony, he had to leave the trade as he was marked as an agitator, but he continued as Honorary Secretary of the union. In 1924 he enrolled at the University of the Witwatersrand for an engineering degree, but had to discontinue his studies because of insufficient means. He first came into contact with garment workers when he was elected Secretary of the Witwatersrand Middlemen Tailors Association on 31 March 1927. He subsequently became the General Secretary of the Witwatersrand Tailors Association.

In July 1929 a new constitution for the union was adopted, the name being changed to the Garment Workers Union, although the name was actually only adopted in 1930. There were 1750 members, two thirds of them factory workers

Sachs immediately tackled the problem of the violation of the agreements of both the Industrial Council for the Bespoke Tailoring Industry and the Industrial Council for the Clothing Industry (Transvaal). He started examining wage registers and prosecuting employers, many of whom were paying irregularly and forcing workers to sign for wages which they had not received. Sachs firmly believed in the law in South Africa and in the following years the Garment Workers Union made much use of the courts to bring employers and enemies of the union to justice.

The union suffered a severe setback in the early 1930s in its fight for better wages. In 1931 there use a general strike which ended inconclusively and left the workers whose earnings were meagre and inadequate in no better position. In 1932 there was another strike of garment workers as a result of demands by employers to reduce wages

Mr Oswald Pirow, then Minister of Justice, took a hard line and used the police force against the strikers. The workers were defeated although the employers achieved only a 10% reduction in wages, compared to their original demand for 25%. Sachs was served with a deportation order which was never enforced, although he was not allowed to live on the Witwatersrand for twelve months. Between 1928 and 1932 there were 100 strikes which to some extent helped to improve conditions or end grievances. In 1934 the bespoke section of the union was dissolved and the tailors formed the Tailoring Workers Industrial Union (Transvaal).

The 1930s and 1940s saw the blossoming of Afrikaner nationalism, and the National Party made a concerted effort to destroy the union which had attracted so many of their people. In 1935 a closed shop clause was included in the agreement. These were also the years which saw the rise and zenith of Fascism in Europe. Fascist groups such as the Greyshirts and Blackshirts used racist ideology to attack the union.

Anti-Semitism was also on the upswing and Sachs was repeatedly accused of being a 'Communist Jew'. It says much for Sachs and the personal loyalty of the workers: towards him, that the union did not succumb. He openly fought back and from 1939 he won a number of defamation cases against the Afrikaans press who were supported by the Nederduits Hervormde Kerk van Afrika. A very bitter struggle was waged in the Germiston branch where the National Party Member for Parliament, Johannes du Pisanie, was active in inciting the workers. The 1940's were a period of bitter struggles for fair wages as also of feuding between the Transvaal garment workers and Cape workers, led by Robert Stuart, who was bitterly opposed to national unity among garment workers

In 1948 the union obtained a forty hour week for the workers

The passing of the Suppression of Communism Act in 1950 caused another crisis in the history of the Union. Its leaders Anna Scheepers (President), Sachs (General Secretary) and Johanna Cornelius were listed as Communists. Sachs appealed on the grounds that he had been a member of the Communist Party from 1921 until August 1931 when he had been expelled from the party for political differences. Subsequently he supported the South African Labour Party. Sachs' banning meant that he could no longer hold his position as General Secretary of the Garment Workers Union, nor could he attend public gatherings

Sachs flagrantly disobeyed these orders by addressing a mass meeting of garment workers on 24 May 1952. He was supported by all the workers who again convened on 26 May after his arrest and condemned his listing as a Communist and his removal from the secretaryship of the Garment Workers Union.

Sachs' position eventually became so intolerable to him, that he left South Africa and settled in England. He died in London in 1976.

Over the years the composition of the union had changed. Whereas in 1938 Coloured workers were 22% of the total membership, by 1953 the union comprised 60% Coloured workers to 40% White. By law the union had had to establish parallel branches, No.1 branches being for Whites and No.2 branches for Coloureds. This has now been reversed and once again the Garment Workers Union is allowed to have combined branches

Johanna Catharina Cornelius Fellner succeeded Sachs as General Secretary and served in this capacity until her death on 21 June 1974. In the first few years of his exile Sachs attempted to continue his fight for the workers in South Africa but lack of support from the Garment Workers Union caused his efforts to peter out. In general this was a quiet period of co-operation and negotiation. It was influenced by the Botha Commission (Industrial Legislation Commission) set up in 1945, and the passing of the Natives (Settlements of Disputes) Act and the Industrial Conciliation Act of 1956. There was a split in the ranks of the union, as the White workers felt that the provisions of the Industrial Conciliation Act would make it impossible for racially mixed unions to operate. They thus formed the Garment Trade Union of European Employees (SA). Other problems to which the union paid attention were job reservation, workers in uncontrolled areas, and the establishment of a training college for garment workers

Another outstanding leader of the union was Anna Elizabeth Scheepers. Born on 18 March 1914 on the farm De la Rey near Krugersdorp, she attended Monument High School but was obliged to leave school in her matriculation year as her family had been severely affected by the depression. In 1933 she started work as a presser in a Johannesburg factory and began to be active in the activities of the Garment Workers Union. In August 1935 she was elected President of the union. Like other trade unionists of the time she visited Russia before the war and C R Swart attempted to list her as a Communist in 1952. She has distinguished herself, receiving a medal for voluntary services in World War II from Field Marshal J C Smuts. In November 1968 she was elected as the first and only woman on the General Council of the International Textile, Garment and Leather Workers Federation. In April 1973 she was awarded the Honorary degree of Doctor of Laws by the University of the Witwatersrand and in 1974 she was elected a Senator.

Besides the struggle for fair wages and a shorter working week, the union was able to obtain for the workers by 1949 three weeks' paid annual leave, whereas in 1928 there had been no such paid leave. In 1928 the only paid holidays were Christmas Day and May Day. In 1949 four other public holidays were added. By creating funds, two important social services were provided namely assistance to the sick and unemployed.

The Garment Workers Union struggled in order to obtain a better life for its members, relying almost entirely on its own strength and the moral support of fellow trade unionists. The union was respected by some employers and feared by others, but its members were treated with respect as they always had recourse to it if they were being mistreated.