In January 1639, the Lords Montrose, Argyll, and others met in Edinburgh to formulate their strategy. While there, they issued orders to the Scottish shires to prepare for war, and an appeal to Scottish soldiers abroad to return and fight under their banners.
http://www.british-civil-wars.co.uk/timelines/1639.htm
As preparations for war began, the Marquess of Huntly rallied those still loyal to the Crown at Kintore in Aberdeenshire.
In response to the Covenanter preparations, King Charles I issued a summons to all English noblemen to attend him in arms at York.
As the preparations for war continued, the prominent citizens of Inverness pledged to support the Covenanter cause.
After the Marquess of Huntly withdrew from a confrontation at Turriff, Covenanter forces occupied the town.
http://www.turriffanddistrict.com/index.php?topicid=4
Following Inverness's declaration of support for the Covenanters, they seized arms and ammunition that the Marquess of Huntly had sent to Inverness Castle.
As tensions continued to build, King Charles I issued a denunciation of the Covenanters in which he directly accused them of treason.
Unable to support his position, the Marquess of Douglas abandoned Douglas Castle to the Covenanters.
As rebellion spread throughout Scotland, Covenanter forces under Alexander Leslie seized Edinbugh Castle for the Covenanters.
Dalkeith Castle was captured by the forces of Lord Rothes on March 23, 1639, the third major castle to fall to the Covenanters in four days. The castle contained the main Royalist arsenal in Scotland, as well as the Scottish crown jewels.
The last castle to fall to the Covenanters in March 1639 was Dunbarton. Control of this castle allowed the Covenanters to deny the use of Dunbarton port (the main port of West Scotland) to the Royalists.
As March drew to a close, King Charles rode to York to meet the army he had summoned, and to prepare for war against the Covenanters.
On the same day that King Charles arrived in York, Lord Montrose occupied Aberdeen for the Covenanters.
As war drew nearer, the Royalist Marquess of Huntly and the Covenanter Earl of Montrose met to negotiate at Fyvie Castle. The negotiations ended with Lord Huntly agreeing to meet other Covenanter lords in Aberdeen.
After further negotiations at Aberdeen, Lord Huntly traveled to Edinburgh to meet with more Covenanter lords. His absence left the Royalist forces in Scotland without a leader
After a week of negotiations in which he refused to join the Covenanter cause, Lord Huntly was imprisoned, despite the fact that he had come under a promise of safe conduct.
One day after the arrest of Lord Huntly in Edinburgh, Lords Saye and Brooke were arrested by King Charles in York for refusing to swear to fight against the Scots.
Shortly before the outbreak of hostilities, King Charles issued a proclamation to the rebels offering amnesty if they laid down their arms within eight days.
The day that King Charles issued his proclamation in York, the Marquess of Hamilton departed with his amphibious force for Scotland, intending to publish the proclamation there. When he arrived at Leith, he was prevented by the Covenanters from landing or publishing the proclamation.
After five days of imprisonment, Lords Saye and Brooke were released. Lord Brooke promptly left York, along with his entire contingent of troops.
The same day that King Charles left London for York, the Marquess of Hamilton headed to Yarmouth to prepare an amphibious force capable of landing behind the Scottish lines.
JavaScript must be enabled to get the map.
