Menzies was an unrivalled advocate: Howard

A great politician requires more than expert oratory skills, Australia's second-longest serving prime minister reckons.

You also need to believe in something and then persuade people of its wisdom.

Robert Gordon Menzies - our longest-serving prime minister - had both, according to John Howard.

What made Menzies great was his unrivalled capacity to argue his case with great political flair, he said.

Mr Howard made the observation as he launched The Menzies Era, a book he has written about a man who was a dominant figure in Australian politics for more than 30 years.

Mr Howard said he was drawn to write the 660-page tome because he felt he had one more book in him following publication of his own political memoir Lazarus Rising in 2010.

Australia had a colourful political history to be proud of, he said.

"Australian history is richer and full of more characters than we give ourselves credit for," he told a launch at Old Parliament House attended by Heather Henderson, the daughter of Menzies, and Tom Hughes, who was in parliament with Menzies in the 1960s as well as numerous Liberal politicians.