Here is a short history of the ROBERTS line.

The Great "Welsh  Tract" consisted of 40,000 acres on the west back of the Schuylkill River, embracing what is now the townships of Lower Marion, Haverford, and Radnor. It had been bought by the Welsh people, many of them from the Northern Counties of Wales, namely  Merionethshire, Denbighshiore, Montgomeryshire and Flintshire around the year 1683. Two Welsh framer  (yeoman), William John and Thomas ap Evan, representatives of a company of friends and neighbors in Wales who had decided to emigrate to Pennsylvania where in Philadelphia at the end of 1697. Hugh Roberts went back to Wales and his account of the land in Pennsylvania brought a new group of people to settle what is now called the Gwynedd area around 1698. William John and Thomas ap Evan were in advance of the main company. They had come to select a place and where regarded as the chiefs, so far as business interest were concerned in the new Gwynedd settlement.

The many company of immigrants sailed from Liverpool on the 18th of April. Their ship was the ROBERT and ELIZABETH, its master being Ralph Williams, and its owner Robert Haydock, of Liverpool, England.  It was not until the 17th of July, eleven weeks after leaving Dublin (they had stopped at Dublin and actually did not set sail for the new world until May 1st), and a total of fifteen weeks after leaving their  homes in Wales that they set foot in the land of their adoption. They stayed with the Welsh settlers already there until the man had prepared shelter and laid in food for the winter.  It was the middle of July to the beginning of November that they finally get settled in their new homes.

In Wales, Gwynedd was, in fact, the stronghold of the Welsh. It was the homes of a large part of the Kymric People,. descendents of those Britons who faced Caesar on the shore of Deal, who, half a century before Christ, crossed from Gaul to invade their land. 

It is estimated that there was more than 100 people, of all ages, arriving as the first immigrants in 1698.

The ordinary Welsh use of the that time was to keep no family name, but change it with each generation, by adopting as the surname the first name of the parent. This custom existed among the Welsh immigrants  at the time of their arrival. The English use of preserving a family name was adopted as time went on in the new world. The five brothers, Roberts, were the sons of Robert Cadwalader. 

They were not Friends at the time of their arrival to the new world but joined the Society soon afterwards.