27 March: Humza Yousaf wins the SNP leadership rival defeating his nearest rival Kate Forbes by 52% to 48% in the second round of voting.

29 March, morning: Humza Yousaf is sworn in at the Court of Session as Scotland's first minister becoming the youngest person to hold the post and the first Scottish Asian and Muslim to hold the office since it was created in 1999.

29 March, afternoon: Humza Yousaf appoints his first Cabinet with new deputy first minister Shona Robison, a close friend of Nicola Sturgeon, replacing Kate Forbes as finance secretary. No role at the top table of government is filled with a politician who did not support his leadership bid.

5 April: Police officers carrying out a long running investigation into SNP finances arrest Nicola Sturgeon's husband Peter Murrell, the SNP's former chief executive, at the couple's home near Glasgow. Officers also search the property, putting up a forensic tent in the front garden of the property. On the same day, officers also search the SNP's headquarters in Edinburgh. Mr Murrell is the first person to be arrested in connection with Operation Branchform, the investigation into how more than £600,000 in donations to the SNP earmarked for an independence referendum had been used. Mr Murrell is released by the police without charge pending further inquiries. 

The Herald:

Police officers outside the home of Peter Murrell and Nicola Sturgeon on 5 April. Photo Andrew Milligan/PA.

18 April, morning: SNP treasurer Colin Beattie, the MSP for Midlothian North and Musselburgh is arrested as part of the same police investigation into the party's finances. Mr Beattie is later released without charge pending further inquiries. He resigns from his role as party treasurer the next day.

18 April, afternoon: Humza Yousaf unveils his new policy programme to the Holyrood. The First Minister announced a major change to education policy with a decision to rejoin two international surveys which the SNP had withdrawn from in 2010. He also shelved his predecessor's proposal for a ban on alcohol advertising, delayed the introduction of the deposit return scheme (the scheme was then abandoned in June until 2025 following a row with the UK Government over its remit) and paused plans for a national care service. He described his agenda as a reset of the government's priorities. However, his speech was overshadowed by Mr Beattie's arrest that morning.

11 June: Nicola Sturgeon is arrested and questioned by detectives for seven hours as part of Operation Branchform. The former first minister is later released without charge pending further inquiries. She releases a statement insisting she is "certain" she has committed no offence and describes the arrest as "a shock and deeply distressing".

12 June: Humza Yousaf refuses to suspend Nicola Sturgeon from the SNP. Critics both inside and outside the party point out that under her leadership party it was usual that figures under police investigation had the whip withdrawn. The First Minister said: "I'll not suspend Nicola's membership. I'll treat her in the same way I've treated, for example, Colin Beattie. Those that have been released without charge I see no reason to suspend their membership."

20 June: Recall petition opens until 31 July in Rutherglen and Hamilton West to determine whether former SNP MP Margaret Ferrier is removed as the MP and a by election called. Should 10% of voters in the area sign the petition a by-election would be called with the vote expected to take place in early autumn. With polls showing rising support for Labour such a Westminster by-election would be a major test for both Humza Yousaf and Scottish Labour leader Anas Sarwar.

24 June: Humza Yousaf addresses his party for the first time since being elected leader. He gives a key note speech to the SNP's independence convention at the Caird Hall in Dundee saying his party would stand at the general election on the proposition that people could "vote SNP for an independent Scotland". There is some confusion about whether he wants the general election to be a a de facto referendum as Nicola Sturgeon had planned. He later clarifies the position: "If we win that general election we will then negotiate with the UK government of how we give it democratic effect. If it is a referendum or simply the general election that is of course for the UK government to determine."