Many of those browsing its stalls through the morning were no doubt already looking forward to watching that afternoon’s Euro 2016 football match between England and Wales.
Work will have been uppermost in the thoughts, however, of the area’s MP, the hugely popular and enthusiastic Jo Cox.
Campaigning may have been in full swing for the forthcoming EU referendum but Mrs Cox was still making time for her regular surgery at Birstall Library, a stone’s throw from the marketplace.
These surgeries, a chance to speak directly with constituents and find out more about their views and problems, are regarded by MPs as one of the most important parts of their weekly routine.
But outside that day’s surgery, at a few minutes before 1pm, the calm of Birstall was shattered by the horrendous attack that was to claim Mrs Cox’s life.
She was shot three times by Thomas Mair and suffered 15 stab wounds as her office manager Fazila Aswat and senior caseworker Sandra Major looked on in horror.
Another witness, Bernard Carter Kenny, 77, was stabbed in the chest after he bravely tried to go to the stricken MP’s aid. Mair then calmly walked away.
Emergency services rushed to the scene and Mrs Cox was taken into an ambulance by paramedics and doctors but, despite their best efforts, she was pronounced dead at 1.48pm. Her last words were reported to be “no, my pain is too much”.
Mair was arrested by uniformed police at around the same time on Risedale Avenue, which is off the A643 Leeds Road and fewer than five minutes’ walk from the library.
He was carrying a holdall that contained the blood-splattered murder weapons.
Back in the centre of Birstall, confusion and no small measure of fear continued to reign.
Word of Mair’s arrest had yet to filter back to the scene of the attack, which remained cordoned off by armed police.
A helicopter hovered above the area while at least one local school was put into lockdown as residents waited anxiously for news that the manhunt was over.
Eye-witnesses were by now also beginning to describe how the afternoon’s nightmarish events had unfolded.
Hichem Ben-Abdallah, 56-year-old owner of the Azzurro café that sits next to the library, said: “I had customers. I was just serving them drinks. Then all of a sudden we heard screaming. I saw a river of people rushing down the hill.
“They were screaming – and pulling someone behind a car. A lady was down.
“The man pulled a gun – it was a makeshift gun not like something you see on television.
“He was kicking her as she was lying on the floor. A brave man tackled him to the floor and he tried to take the gun off him. But he couldn’t and another shot was fired, it’s lucky he wasn’t shot.
“After the second shot I turned and ran. He walked away very calmly, down the steps. Nobody stopped him – he had a gun.”
Mrs Cox was formally identified by her sister, Kim Leadbeater, at a mortuary in Bradford.
At West Yorkshire Police’s Carr Gate headquarters in Wakefield, it fell to Temporary Chief Constable Dee Collins to publicly confirm news of the MP’s death at a packed and emotionally-charged press conference.
Grim-faced, she told journalists that she wanted to express her “deepest sympathies to [Mrs Cox’s] family and friends at this tragic time”.
Sitting alongside her, West Yorkshire’s Police and Crime Commissioner, Mark Burns-Williamson, paid tribute to Mrs Cox and hailed her as “such a talented young woman”.
The country was left shell-shocked – but across the late MP’s Batley and Spen constituency, people almost immediately started pulling together.
Hundreds of people packed into St Peter’s Church on Kirkgate in Birstall that evening to remember Mrs Cox and mourn her devastating death.
Those at the church included MPs Yvette Cooper, Rachel Reeves, Dan Jarvis and Caroline Flint.
They listened as the Vicar of Birstall, the Rev Paul Knight, said the day had been a reminder of the “fragility of civilisation”.
But he said that, even in times of despair, it should be remembered that “there is no escape from the love and mercy of God”.
A candle was lit and prayers were said while there were also periods of quiet reflection.
The Rev Knight recited Psalm 23, The Lord Is My Shepherd, before leading the singing of Lord Hear My Prayer.
And, as dusk turned to darkness in the centre of Birstall, flowers were already beginning to build up at the marketplace’s Joseph Priestley statue as members of the community showed their sorrow at the loss of one of their own.