52 Ancestors in 52 Weekes DNA Connection Week #8

I was lucky enough to get one of my 5 brothers to do the Y DNA test with FamilyTree before the end of the year.  We recently got the results back and even though I have very little knowledge on what any of it means I was able to determine that we had 2 possible hits.  The one was a long way back and I have not yet contacted him.  The other was between 4 & 8 generations.  We have been in in touch but have not been able to find the common link for sure but it does involve his ancestor, the warrior COSSACK's and my KOSACK ancestors. 

 Now in getting my immigrant ancestors Military papers for his time in the Union Army during the War between the states I found many spellings of his last name and COSSACK was among them. My ancestors came from Prussia according to those same papers and from the Ship List where I found they came to the USA.  According to the ship they sailed from Bremen and were passengers on the Johannes.  They arrived in Baltimore in January 1859.  One of them had previously arrived in the USA.

I told the contact that my ancestors were from Prussia and he responded his was from Kiev, Ukraine.  Now I am almost certain there is a link somewhere.  I have no idea where my ancestors were prior to Prussia and how long they were there.  My contact then responded that he was able to determine that his ancestor was in Prussia for a short period.  I don't know how long.

I had responded that 3 of the male Kosack's that came here to the USA had enlisted in the military and 2 of the three went in with higher ranks.  My great grandfather was only 16 so I'm fairly sure he did not have much experience.  He was a private.  I never met my great grandfather and my grandfather was never talk about his father so I knew very little about them.  I hope to some day find where they really came in Europe.  That is my main goal in doing my genealogy.