If the Union "in connection with" used in the beginning of the sentence in the meaning of the word "because" all parts of the Union are written separately. After the associated words (the more sentences) a comma: "In connection with the modernization of production, some employees were sent on vacation. "Due to the fact that you never come to work on time, I instructed Nicholas".

The accent in this case falls on the second syllable of the word: in Swazi.
Along the same line, but at the end of the sentence, the accent remains on the same place, but no comma is used: "He was dismissed in connection with a categorical unwillingness to do their job". The exception for difficult subordinate sentences: "the Prosecutor came in because a neighbor wrote a complaint against me".
If the expression is used in proximity, contact, all parts are still written separately: "the President of the company was suspected of ties with the criminal world."

The stress falls on the first syllable: Swazi.