1: Second Industrial Revolution
2:massive urbanization
3:productivity, profit and prosperity.
Territories west of the Mississippi, which angered the North as free states could now be slave states
Most of the population in England migrated to cities in the late eighteenth century because of better jobs. In the late 18 century, people forcibly driven from the land into factories by 'enclosure'. Landless, the agricultural labourers who remained were powerless to prevent explotation and were therefore forced to work for long hours for meagre, irregular wages.
You can check in Acts 13:5 that John, or Mark, was accompanying Paul and Barnabas. John eventually left them though, as it can be seen in Acts 13:13.
<em>"From Paphos, Paul and his companions sailed to Perga in Pamphylia, where John left them to return to Jerusalem" </em>
When Paul and Barnabas planned another trip, Barnabas wanted John to accompany them, but Paul refused. He did not want someone who left them. Because of that, they went separated ways. Paul went with Silas, Barnabas with Mark.
When Paul wrote a epistle to the Colossians, he included a commendation of Mark in (as you can see in Colossians 4:10). It most likely means that the earlier contention was eventually resolved.