What you consider as "important" or "major" events will determine the answer here.  This will be different for different people.   I would configure my timeline with being able to start with a fixed number of events.  The first would be Bert Cates’ teaching of evolutionary theory, which lands him in jail.  I would say that the next major event is he being charged with violating the law in his teaching.  Although it is minor, I say that Rachel coming to visit Cates in jail is a major moment.  For me, the arrival of Matthew Brady and Mrs. Brady into Hillsboro is really important.  The indication that Drummond is going to represent Cates is another critical event in the drama, sponsored by Hornbeck’s paper.   From this point, I think that the reader is going to have to make some calls as to what they consider major events.  If one considers the relationship between Rachel and Cates as important, then I think that some major events would have to be included here.  If one considers the relationship between Drummond and the Bradys as essential, inclusion of these events could be included.  At the same time, the rise of the Reverend and his relationship to his daughter and Cates might be incorporated. If one wanted to place primacy on the relationship between Hornbeck and the various characters, I think that it would be appropriate if one considered it to be major. Certainly, the trial would have to be included as a major event and the back and forth in different contexts between both advocates would be included.  I would also include the cross examination of Brady by Drummond.  The ending of the trial, Brady’s heart attack, as well as the closing of the play with Drummond holding both books of Darwin and the Bible together and placing them in his bag as he leaves would be important.