Nicola Sturgeon has been one of the biggest politicians in Scotland since devolution and has certainly become the most well-known.

While Alex Salmond took the SNP from the fringes of Scottish politics, with limited electoral success to a party of government and grew support for independence to make it a realistic possibility, Sturgeon took it to a new level of popularity and seeming electoral invincibility.

She was able to harness the upsurge in support for independence after the 2014 poll in a way few others could have.

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Party conferences became huge affairs at venues normally reserved for global rock stars and membership went through the roof.

Election after election, saw the SNP emerge as the winner in Scotland and her position as leader was rock solid.

Her journey took her from failing to win her early attempts at election in Glasgow, to the SNP’s biggest electoral asset ever.

Sturgeon’s popularity ratings as a party leader and First Minister regularly blew the other leaders at Holyrood and Westminster out of the water.

Since the last Holyrood election, however, cracks in that invincibility began to show with Ian Blackford ousted as Westminster group leader, and rows over the independence strategy splitting the party and the Gender Recognition Reform Bill providing further splits.

Over her time as First Minister though, there has been plenty of other events that could have derailed a First Minister but didn’t, not least the Alex Salmond court case and subsequent inquiries.

Other Ministers resigned over scandals, like Mark McDonald and Derek Mackay but Sturgeon's position was never seriously threatened.

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Throughout, she has consistently been lauded for her understanding of the issues and her ability to communicate and connect with the public.

While there are many who are, at best less than complimentary about her, and at worst downright hateful, Nicola Sturgeon has been respected and admired by more people in a way that most politicians in the UK would love to enjoy.

Not everything has gone according to plan, however.

When Nicola Sturgeon came to office as First Minister, she said it would be her defining mission to close the poverty-related attainment gap.

She said it would be her government’s “defining mission”.

But as she leaves office it cannot be described as mission accomplished.

She also said she would be judged on efforts towards the aim of eradicating child poverty.

Measures like a new Child Poverty Bill were introduced, money targeted at early years interventions and latterly the Scottish Child Payment was brought in.

But child poverty rates remain stubborn and in Glasgow, one in three children is living in poverty and in the most deprived areas it is as much as one in two children.

She also famously admitted to having “taken her eye off the ball” on drug deaths as Scotland recorded the highest rates in Europe, with year-on-year record high totals of people dying.

The most high-profile period of her time as First Minister was the covid pandemic.

READ MORE: Nicola Sturgeon urged to intervene in Glasgow budget as huge cuts loom

She led the covid response in Scotland, speaking daily at news conferences throughout as cases rocketed and then fell.

She had the task of announcing the lockdown in Scotland and the at times confusing different local approaches as the pandemic developed.

Sturgeon was widely praised for her calm response compared to the UK leadership of Boris Johnson as Downing Street descended into chaos.

In the last year, the independence debate came back to the forefront after the pandemic.

A plan to have a second referendum was blocked by the UK Government and the Supreme Court ruled Holyrood couldn’t declare a legal referendum without Westminster’s approval.

The final months of her time as First Minister will be remembered for the row over the Gender Recognition Reform Act.

It too has been blocked by Westminster after ministers used their powers to deny it going forward for Royal Assent.

While both provided opportunities for highlighting the UK government was denying the democratic mandate of the Scottish Parliament it did not take the SNP any further forward in achieving a referendum or how to achieve independence.

The GRR debate became more intense as a double rapist who identified as a woman after being convicted was held in a women’s prison before sentencing, prompting outrage and forcing the prisoner to be moved to a male prison.

In her time as First Minister Nicola Sturgeon has been at the wheel through some of the most turbulent times with covid and Brexit.

She has, unlike most leaders stepped down at a time of her own choosing and for whoever becomes First Minister she will be an almost impossible act to follow.