The names of the months in english (as well as in many other languages) come from latin words.
January - this month was dedicated to Janus, the Roman god of doors. Janus had two faces one, look back at the old year and the other looking forward to the new year.
February- Februarius- Februa was the Roman purufication festival, which took place at this time of year.
March- Martius- from marsm the Roman god of war.
April-Aprilis- from aperire, Latin for open, during this month.
May- Maius-probably comes from Maia, the Roman goddess of growth and increase.
June-Junius- either from a Roman family name Junius, which means young, or perhaps the goddess juno.
July- Julius- after Julius caesar. This month was named caesar's honour by Mark Antony in 44 BC. previously this month was called Quintilis from the word quintus, five, as it was the fifth month in the Roman Calendar.
August- Augustus - named in 8 BC in honour of emperor August.
September- September - from septem, seven, because it was the month in the roman calendar.
October- October- from octo, eight, (as in octopus, which has eight legs), the ight month in the Roman Calendar.
November- November - from novem, nine, the ninth month in the Roman calendar.
December -December- from devem, ten, the tenth month in the Roman calendar.