Irish travellers

[Loretogirl47]

How does one find out any information on someone who was an Irish traveller.  My 2x g. Grandfather, John Peter McCreesh on his marriage certificate lists his father as John McCreesh and occupation as traveller.  Would any record of the travellers have been documented, this would be around 1800 and forward as my G grandfather was born in 1824.   Any help or ideas appreciated, thanks in advance.

[dathai]

Irish Traveller i think is a modern day term applied to the traveller's they may have been called tinker's in early 1800's'
The term Irish Traveller in your ancestor's case may have a total different meaning.

Example
http://www.census.nationalarchives.ie/search/results.jsp?searchMoreVisible=true&census_year=1911&surname=&firstname=&county19011911=&county1821=&county1831=&county1841=&county1851=&barony=&parish=&ward=&townland=&houseNumber=&familyId=&ded=&age=&sex=&search=Search&ageInMonths=&relationToHead=&religion=&education=&occupation=traveller&marriageStatus=&yearsMarried=&birthplace=&nativeCountry=&language=&deafdumb=&causeOfDeath=&yearOfDeath=&familiesNumber=&malesNumber=&femalesNumber=&maleServNumber=&femaleServNumber=&estChurchNumber=&romanCatNumber=&presbNumber=&protNumber=&marriageYears=&childrenBorn=&childrenLiving=

[mmcpadden1]

Could probably refer to a commercial traveller,who called to  retailers for orders.I have heard of travelling salesmen too who called to householders selling a variety of wares