When Does "The Kents" #4 (1997) Take Place?

"The Kents" #4 "Bleeding Kansas" Part 4 is a western historical fiction comic-book written by John Ostrander that released September 3rd, 1997. So when is "The Kents" #4 set? 

It takes place on the fictional DC Comics Universe timeline in the year: 

1857 AD - 1860 AD 

We know this because Jonathan "Pa" Kent writes to Kal-El/Clark Kent/Superman, "Clark, the nearest I can figure is that this all happened summer or fall in 1857.", referring to the second scene. So it's most likely 1857 AD at the beginning of the book. 

Later, in the main action, Tobias Freeman says, "Paper's been full about that massacre over t' Marais de Cygnes.", which happened in the real world on May 19th, 1858 AD. So it's during or just after May of 1858 AD at this point. 

Pa Kent tells Clark (and us), "We have no journal entries or letters for a long time at this point."... "However, there are some newspaper clippings from this time in the scrapbook." The following page covers some real world historical events including abolitionist John Brown's famous and tragic raid on Harpers Ferry, which he states occurred "On October 16, 1859" is perfectly lined up with the date of its start in the real world. It lasted until October 18th, 1859 AD. These events are depicted in images and Pa wonders if his ancestors were involved in any of these historical moments as they had been in previous ones. This short segment therefore takes place in 1859 AD. 

Finally, at the start of the second-to-last scene in the book, there's a textbox reading 'From the diary of Mary Glenowen-- "December 13, 1860'. Considering there are three more textboxes previous to it with 1860 dates, we know it is almost certainly 1860 AD at the end of the story. 

Additionally, the comic opens with a frame prologue and includes three short interludes extending the setting with Pa Kent from issues #1 and #2 which had textboxes telling us it’s "Metropolis, today." So the frame story is set in ‘the present’ of the DC Universe. 

It is a chronologically early comic in the DC Comics Universe multiverse timeline and can be read at its timeline point after the previous issue, "The Kents" #3 (1997).