January is the first month of the year. January is named for Janus, the Roman god of doors and gates. Also, the word 'janitor', with the previous meaning of 'doorkeeper', comes from the name od two-faced Janus.
The names of February comes either from the Roman god Februus or else from 'februa', the festivals of purification celebrated in Rome every fifteenth of this month.
March is named after Mars, the Roman god of war. The connection is even easier to make in French, where March is simply 'Mars'.
April is named in honour of the ancient goddess of love, Aphrodite. Another theory is that the name could come from the Latin word 'aperire', meaning 'to open', referring to flowers opening in spring.
May is likely to have been named after the Roman goddess Maia, though there is a theory that May might have its name from the Latin 'Maiores', meaning 'Seniors'.
June gets its name from the Roman goddess Juno, the wife of Jupiter. She is goddess of marriage. Because of this, getting married in June was thought to be lucky.
July was named after Julius Caesar, the general and statesman, later dictator of the Roman Republic.
August is named after the first Emperor of the Roman Empire: Gaius Julius Caesar Augustus, who became Roman consul in this month
September is named for the Latin word 'sept' for 'seven' (it was the seventh month of the year, before January and February were added to the beginning of the year.)
October's name comes from the Latin 'oct' for 'eight'. It was the eighth month of the year before January and February were added to the beginning of the year.
November's name is from the Latin word 'novem', which meaning 'nine'. It was the ninth month of the year before January and February were added to the Roman Calendar.
And the last month of the year - December - with the name of the month coming from the Latin 'decem' for 'ten', it was the tenth month of the year before January and February were added to the Roman calendar.