She became active in campaigning for Scottish independence through her membership of the Glasgow University Scottish Nationalist Association, and came to prominence in 1967 when she won the Hamilton by-election as the Scottish National Party (SNP)candidate. A practicing solicitor at the time of her election, she proved to be a sound choice as her eloquence and ability bolstered a hard fought SNP campaign and saw her through to victory.
She famously said at the time of her election, 'stop the world, Scotland wants to get on', and her presence at Westminster proved to be a real focus for the SNP with a significant rise in membership being the result. Furthermore, many political commentators speculate that it was as a result of her victory that the then Labour Government established the Kilbrandon Commission to look into the establishment of a devolved Scottish Assembly.
Despite her high profile she was unsuccessful in retaining the Hamilton seat at the 1970 General Election, but she managed to be re-elected to Westminster at the February 1974 Election. She remained a MP until 1979 when she became a MEP.
It was during her time as a MEP that she acquired the nickname Madame Ecosse (French for Mrs Scotland). The term was meant to be given in jest and used in a disparaging way by her opponents, but Ewing used the term as a badge of pride and it stuck.
In 1999 she gave up being a MEP and became a MSP in the first session of the Scottish Parliament, representing the Highlands and Islands. As the oldest member it was her duty to preside over the opening of the Scottish Parliament, a session she opened with the famous words, 'The Scottish Parliament, adjourned on the 25 th day of March in the year 1707, is hereby reconvened'.
In 2003 she lost her husband, Stewart Ewing in a fire accident. He had been active with her in politics for many years, and had himself served as a SNP councillor for the Summerston area in Glasgow. The same year she lost her husband she stood down from being a MSP, although she continues to serve as the SNP's President, a position she has held for many years.
Her son Fergus Ewing and his wife Margaret Ewing both serve as SNP MSPs, whilst her daughter Annabelle Ewing is a SNP MP.