The man who demands
Kohli brought to the captaincy of India an ambition that previous captains had not, but that ambition was in keeping with the progression from Sourav Ganguly to Rahul Dravid to MS Dhoni to Kohli: ambition consistent with India's resources and financial standing as a cricket nation. India stayed No. 1 for 18 months under Dhoni, but back then, they were fighting champions at best, hanging on to the ranking as opposed to owning it.
Dhoni would always seem resigned to his bowlers' limitations. Bigger tests will come - in turning conditions, Kohli has found two bowlers who have no limitations - but Kohli doesn't seem like a captain who will settle for mediocrity from his bowlers, shrug his shoulders and try to save Tests. He will demand more. He will, in partnership with coach Anil Kumble, look to provide his bowlers the best environment so he can demand more. He has consistently played five of them, so they are always fresh, and he has led the batsmen from the front when it comes to taking on the extra responsibility brought on by the fact that there are five bowlers.
Under Kohli, India won nine of their 12 Tests in 2016. The other three were drawn, two of them thanks to weather. The Test side had a belief that had been missing in the months leading up the start of Kohli's captaincy. It was a time when India would compete for long durations in a Test, and then collapse without any check. In his own words, Kohli said he rid the system of quests for personal success, which came in the way of dominating when the team was doing well, and of fighting when it was collapsing. Under Kohli, India's intensity never fell. The team mirrored the captain.
In modern cricket, where there is so much input from coaches and data analysts, a captain's vision for a team becomes more significant. In the year 2016, Kohli's vision for India's Test team was 20-20.
India made significant decisions in two parts in 2016. First, Cheteshwar Pujara and M Vijay were dropped on the tour of the West Indies for more flamboyant options. Pujara was even told that he needed to work on his intent: he was fighting at the start of his innings, which was exactly what India needed, but India needed some dominance from him once he was set. Pujara came back a more assertive player, albeit in the home series, and Vijay made a successful return too. What was crucial for Kohli was to admit that he still needed these players, though he may have asked them to sit out earlier.
1 Number of balls Kohli hit in the air off the 805 deliveries of spin he faced between September 25, when he got out to an aerial shot off a spinner, and December 10. (And that one shot was after India had reached safety in the Mumbai Test after conceding 400 on a turning track.)
What they said
"Kohli's influence is likely to be profound on the type of Indian cricketer to come, and therefore on the nature of cricket that India will play in future […] India's seamers have bowled more quickly and aggressively than England's and the ground fielding has been just as intense, areas where traditionally England might have expected an edge." - Michael Atherton, in the Times, during the England series
"The difference between MS and Virat is the generation. Virat is one who wants to be at the front. He leads from the front. He says things to your face. You are not going back to the room thinking, 'what he is thinking' or what the team is thinking about oneself. He lets you know upfront and there is a lot of clarity." - R Ashwin
The closest contenders
Faf du Plessis
Du Plessis took South Africa to yet another historic Test series win in Australia, preceded by a 5-0 ODI whitewashing of Australia in South Africa.
Misbah led Pakistan to a well-fought drawn series in England, and a home series win against West Indies.
Sidharth Monga is an assistant editor at ESPNcricinfo