Spiegl was born near the Hungarian border in the village of Zurndorf, Burgenland, Austria, where his father was a businessman manufacturing among other things carbonated water. Spiegl attended the Gymnasium in Eisenstadt but, as the family were Jewish, they soon found themselves being persecuted by the Nazis in the wake of the Anschluss of 1938. All their property having been confiscated, Fritz's parents succeeded in leaving the country in 1939, eventually escaping to Bolivia while sending Fritz and his older sister Hanny (born 1923) to England, where, in Northamptonshire, they received a warm welcome.

Every Saturday, for eight years, Spiegl would discuss such matters as the use of the word "lie", the flagrant misuses of parliamentary language, the prevalence of tautology in popular speech and the verb "jubilize" as it was employed during Queen Victoria's Golden Jubilee. He would even meditate on the habit of young doctors wrapping their stethoscopes in a U round their necks rather than in a Y configuration, as depicted by the Telegraph cartoonist Matt.

Reading every national newspaper every day, he continued to accumulate knowledge and anecdotes throughout his life. His sure-footed negotiation through the linguistic jungle in an accented English made him immediately recognisable on the television or wireless; this was all the more remarkable since he had arrived in Britain shortly before the Second World War speaking no English, and was later stricken by impaired hearing.

A native speaker of German, Fritz Spiegl did not speak a word of English when he moved to England as a 13 year-old -- a fact which has often been regarded as the trigger for his preoccupation with language phenomena such as, say, malapropisms and for the biting yet humorous linguistic purism of his later years. As one commentator remarked, Spiegl

...soon knew a great deal more about the language than most English people do. And cared more too. One can understand this. It's galling, when you've taken the trouble to learn that "an alibi" is not the same as "an excuse", to find that the natives themselves seem to have forgotten the difference.

On arrival in Britain, Spiegl was sent to a public school, where he learned little beyond "rugger, plane-spotting and a bit of Latin". Eventually he went to London to work for an advertising agency. But he soon switched to music, taught himself to play the flute, enrolled at the Royal Academy of Music and, within a short time, became principal flautist with the Royal Liverpool Philharmonic Orchestra, a position he kept for more than a decade. Ear damage appears to have played a part in his exit from professional playing, as in later years he would occasionally refer to having been "invalided out by the brass section".

However, during that time he also pursued other interests and began his association with the BBC, aiming to be a popularizer of classical music. A resident of Liverpool, he organised annual Nuts in May concerts, featuring a Liszt Twist and other parody items. This approach helped draw new young audiences into concert halls. Less attracted to pop music, Spiegl once called the Beatles phenomenon "the greatest confidence trick since the Virgin Birth". However, he used to be tolerant towards journalists who, up to his death, often misspelt his name Spiegel, Spiegle, Speigl, Speigel, or Speigle.

Fritz Spiegl died suddenly during a Sunday lunch with some friends and his wife, Ingrid Frances Spiegl in Liverpool.