Born February 22, 1857, London, Robert S. S. Baden-Powell was a British army officer who gained fame during the Boer Wars in South Africa. He was instrumental in the 217 day defense of Mafeking. You may not know the name, but you know the Organization he founded; The Boy Scouts. Today marks the anniversary of the formation of the first official Scout troop.
Following the Boer war, he authored a book, Scouting for Boys, that was published in 1908. That book was essentially a rewrite of his earlier book Aids to Scouting. That book drew heavily on his experiences in the British army. Following the siege of Mafeking this military handbook unexpectedly became popular with many youth groups and educators.
Baden-Powell copied many ideas for the rewrite from Ernest Thomas Seaton, the founder of the boys group the Woodcraft Indians. Seaton would go on to become the Chief Scout of the BSA.
The Boy Scouts were originally for boys between 11 and 15 years of age. Baden-Powell would go in to form the Wolf Cubs, known as Cub Scouts in the US, for younger boys in 1916. His sister Agnes would help found the Girl Guides in late 1910, after the Scout Rally at the Crystal Palace in September of 1909.
In the first part of Scouting for Boys, Robert Baden-Powell explains the meaning of the phrase:
The scouts’ motto is founded on my initials, it is:
BE PREPARED,
which means, you are always in a state of readiness in mind and body to do your DUTY;
Be Prepared in Mind by having disciplined yourself to be obedient to every order, and also by having thought out beforehand any accident or situation that might occur, so that you know the right thing to do at the right moment, and are willing to do it.
Be Prepared in Body by making yourself strong and active and able to do the right thing at the right moment, and do it.
— Lieut. Gen.Baden PowellC.B., Scouting for Boys (1908)