The First was absolutely tragic The Entire McKinnons included the in laws were slaughtered by Mulciber, Nott, Travers and Karkaoff and Voldemort
The Bones Family was totally destroyed only Susan’s Parents and Aunt and Susan herself lived. her three grandparents, her cousins and Uncle Edgar Bones were murdered in their own pool of blood
The Prewett Twins were hit with various Curses
Fenwick was torn to pieces by Lestrange-Black and Rosier
Dearborn was missing and killed presumably by Voldemort
Dorcas Meadows was slaughtered by Voldemort personally
So that is why an edict was announced by Crouch Senior in August
Meadows Murder I suspect was around January 31st and February 1st
Prewetts Murder was around April-May
The Bones Family Slaughter around July 28th
The McKinnon Massacre was taken place around 31st July Harry’s Birthday so Marlene McKinnon and many in laws and any siblings were likely slaughtered one by one
Fenwick Mutilation Benjy Fenwick was shredded by 3 D.Es
Dearborn goes missing and presumably slaughtered by Voldemort
The Murders of millions of Muggle Families
The Potters are killed the war ends on 1st November
The Longbottoms are repeatedly attacked by the cruciatus curse
War comes a close if Marlene McKinnon, Edgar, his wife and children had survived Voldemort would’ve slaughtered Edgar, Amelia and their wives and brother and Marlene McKinnon her brother and sister in law except two or 4 children
So the McKinnons are basically extinct the Bones Family has no other male heirs unless Susan has a boy with Ernest Macmillan
If Voldemort had stuck to murdering the Muggle Population the whole order would’ve had a large and powerful place in Wizarding History with these powerful people
Edgar, Amelia and Susan’s Father
Marlene and her brother
Sirius Black
James Potter and Lily Potter
Alice and Frank Longbottom
Caradoc Dearborn
Benjamin Fenwick
Dorcas Meadows
Gideon and Fabian Prewett
Arthur and Molly Weasley
Severus Snape
Remus and Nymphadora Lupin
Elphias Doge
The Weasley Twins
Ron and Hermione Weasley
Harry and Ginny Potter
Neville and Hannah Longbottom
Ernest and Susan Macmillan
Cousins by Edgar Bones
The Weasleys
Hestia Prewett Née Jones
Emmeline Prewett Née Vance
Sturgis Podmore
Aberforth Dumbledore
Gellert Grindelwald
and Many more while some of them written above would still be killed but in a different timeline the war ends in 2030 since the Bones, Longbottom, McKinnon, Potter, Weasley, Lupin, Prewett and more families like Jordan, Abbott, Bell, Wood etc etc would have fought all bravely
That’s why both wars were brutal The Black, Bones and Vance Murders made it weak for The Ministry and The Order of The Phoenix