http://encarta.msn.com/find/Concise.asp?ti=00ACE000
http://www.usflag.org/the.pledge.of.allegiance.html
http://ddi.digital.net/~kenaston/Patr/Pledge.html
first published in 1892 by Francis Bellamy, a christian socialist. an early proponent of the marketing strategy of "creating wants", he distributed the pledge in order to sell flags to schools. Bellamy was a baptist minister, but eventually left the church over it's position on equality for blacks.
the original salute resembled the roman or nazi salute.
"I pledge allegiance to my flag and to the republic for which it stands: one nation, indivisible, with liberty and justice for all."
"my flag" changed to "the flag of the United States of America" in 1923
congress first recognised the pledge in 1942.
in 1943 the supreme court ruled that declining to recite the pledge was legal and not disrespectful.
"under God" was added in 1954.

the pledge appears to have everything to do with marketing, and little to do with patriotism or god.