Question: Who was king of Sweden during the Battle of Kirchholm?

Context paragraphs:
Liturgical Battle: The Liturgical Battle (Swedish: "Liturgiska striden") was the name for the period from 1574 until 1593 in Sweden, when there was a struggle about the confession of faith and liturgy of the Church of Sweden, brought about by the attempts of King John III of Sweden to make the Swedish church take a position in between Catholicism and Protestantism.  The battle began in 1574, when the king introduced some new rules in the liturgy which was not in accordance with Protestant opinion, followed by his publication of the "Liturgia Svecanæ Ecclesiæ catholicæ & orthodoxæ conformia" commonly called the "Red Book", which re-introduced a number of Catholic customs.  The Liturgical Battle ended with the Protestant confession of faith at the Uppsala Synod in 1593.

Battle of Hova: The Battle of Hova was fought in Hova, Sweden on 14 June 1275 between peasants commanded by Valdemar of Sweden and Danish cavalry commanded by Magnus III of Sweden and his brother Erik.  The result was that Valdemar had to flee to Norway and Magnus became king of Sweden as Magnus III.  It was a part of the war against Valdemar Birgersson which was a conflict between Magnus III of Sweden and Valdemar Birgersson.  Magnus was supported by the Danish crown with at least a 100 men (source is unsure).

Battle of Stångebro: The Battle of Stångebro, or the Battle of Linköping, took place at Linköping, Sweden, on 25 September 1598 (O.S.) and effectively ended the personal union between Sweden and the Polish–Lithuanian Commonwealth, that had existed since 1592.  In the battle, an army of c. 8 ,000–12,000 commanded by Duke Charles defeated a mixed force of c. 5,000–8,000 consisting of an invading army of mercenaries in the king's employ and diverse but poorly co-ordinated supporting Swedish noblemen's forces commanded by King of both Sweden and the Polish–Lithuanian Commonwealth Sigismund III Vasa, who was acting to maintain and restore his personal union against anti-Catholic forces in Lutheran Sweden.  The Swedish kings general Constantin fought at the western bridge.

Gustavus Adolphus Day: Gustavus Adolphus Day (Swedish: "Gustav Adolfsdagen") is celebrated in Sweden and some other countries on 6 November in memory of King Gustavus Adolphus of Sweden, who was killed on that date (old style) in 1632 at the Battle of Lützen in the Thirty Years' War.  The day is named for the king and is a general flag day in Sweden and in Finland.  The day was formerly celebrated with torchlight processions and patriotic speeches.  Today what remains is mainly the consumption of the Gustavus Adolphus pastry ("Gustav Adolfs-bakelse" in Swedish) on this day, with a chocolate or marzipan relief of that king on top.

Battle of Gniew: The Battle of Gniew or the Battle of Mewe was fought during the Polish–Swedish War (1626–1629), between Sweden and the Polish–Lithuanian Commonwealth from 22 September with initial skirmishes, to the main battle of 1 October 1626.  Both the Swedish and Polish army were commanded by their kings – Gustavus Adolphus of Sweden and Sigismund III Vasa.  The battle ended with a victory for Sweden.  However, Polish and Swedish armies had different objectives.  Sigismund Vasa wanted to protect Gdańsk from besieging.  Gustav had to protect Gniew, which was important for the prestige for his army.

Swedish neutrality: Swedish neutrality refers to Sweden's former policy of neutrality in armed conflicts, which was in effect from the early 19th century, until 2009, when Sweden entered into various mutual defence treaties with the EU, and other Nordic countries.  In 2016 Sweden became a "NATO Affiliate" (not member), and signed a treaty allowing NATO operations to take place within the country's borders.  Sweden's previous neutrality policy had originated largely as a result of Sweden's involvement in the Napoleonic Wars during which over a third of the country's territory was lost, including the traumatic loss of Finland to Russia.  Resentment towards the old king precipitated a "coup d'état" and the new regime formulated a new foreign policy which became known as "The Policy of 1812".  Since the time of the Napoleonic Wars, Sweden has not initiated any direct armed combat.  However, Sweden's military and government have been involved in major peacekeeping actions and other military support functions around the world.  The accession to the European Union in 1995 meant that neutrality as a principle was abolished.  Sweden is still today a neutral and non-aligned country in regard to foreign and security policy.  However, it maintains strong links to NATO.

King Diamond discography: The discography of King Diamond, a Danish heavy metal band, consists of twelve studio releases, two live albums, five compilations, six singles, and four music videos. King Diamond was formed in 1985, after the dissolution of the group Mercyful Fate, by vocalist King Diamond, guitarists Andy LaRocque and Michael Denner, bassist Timi Hansen, and drummer Mikkey Dee.  The following year, the band released their debut album "Fatal Portrait", which charted at number 33 in Sweden.  King Diamond's second studio album, "Abigail", was released on February 24, 1987, and reached number 123 in the US, number 39 in Sweden and number 68 in the Netherlands.  Following some line-up changes, the group released the album ""Them"" in 1988, which peaked at number 38 in Sweden, number 65 in the Netherlands, and at number 89 in the US, making ""Them"" King Diamond's highest charting album in North America.  The following year, the band released the follow-up album "Conspiracy", which charted at number 111 in North America, number 41 in Sweden and at number 64 in the Netherlands.  In 1990, after more line-up changes, King Diamond released the album "The Eye", which only charted at number 179 in the US, which makes "The Eye" King Diamond's lowest charting album in North America.

Hällestad Runestones: The Hällestad Runestones are three runestones located in the walls of Hällestad Church in Torna-Hällestad, about 20 kilometers east of Lund in Skåne, southern Sweden.  Their Rundata identifiers are DR 295, 296, and 297.  DR 295 is notable because it is held to be raised in memory of a warrior who fell in the legendary Battle of the Fýrisvellir, near Uppsala, Sweden between the Jomsvikings led by Styrbjörn the Strong and Styrbjörn's uncle Eric the Victorious, the king of Sweden, c. 985.  The other stones were raised by the same people, and they probably formed a monument together in memory of comrades lost in the battle.

Battle of Kirchholm: The Battle of Kircholm (27 September 1605, or 17 September in the Old Style calendar then in use in Protestant countries) was one of the major battles in the Polish–Swedish War.  The battle was decided in 20 minutes by the devastating charge of Polish cavalry, the Winged Hussars.  The battle ended in the decisive victory of the Polish-Lithuanian forces, and is remembered as one of the greatest triumphs of Commonwealth cavalry.

Polish–Swedish War (1600–11): The Polish–Swedish War (1600–11) was a continuation of struggle between Sweden and Poland over control of Livonia and Estonia, as well as the dispute over the Swedish throne between Charles IX of Sweden and Sigismund III of Poland.

Supporting paragraphs: Battle of Kirchholm Polish–Swedish War (1600–11)
Answer: Charles IX