Lieutenant Colonel Kronjaeger was raised in Waller, Texas and attended Texas A&M University. He completed Marine Officer Candidate School in 2004, and in 2005 he graduated with a degree in Speech Communication and was commissioned as a Second Lieutenant.
 
In 2006, Lieutenant Kronjaeger attended The Basic School and Infantry Officer Course, then was assigned to 1st Battalion, 3D Marines. He deployed twice to Iraq and conducted counter-insurgency operations in Haditha and Karma, in Rifle and Weapons Platoon Commander billets.
 
In 2009 First Lieutenant Kronjaeger reported to USSTRATCOM, Joint Information Operations Warfare Center in San Antonio, TX, where he was an Information Operations Planner on the USSOUTHCOM and USSOCOM Support Teams. Captain Kronjaeger deployed to Afghanistan with the Joint Special Operations Command as an Information Operations Planner in 2011.
 
From 2011 to 2012 Captain Kronjaeger attended the Expeditionary Warfare School in Quantico, VA, then was assigned to 1st Light Armored Reconnaissance Battalion, where he served as the Company Commander of Company B.  In 2013, Company B deployed with Battalion Landing Team 1/4 on the 13th Marine Expeditionary Unit. Upon return from deployment, Captain Kronjaeger served as the 1st LAR Battalion Operations Officer.

From 2015 to 2018 Major Kronjaeger served as the Inspector-Instructor for Company B, 1st Battalion, 23D Marines in Bossier City, LA. In 2017, he led the unit's participation in NATO Exercise Baltic Operations in Poland, Germany, and Latvia. 
 
From 2018 to 2019 Major Kronjaeger attended the Marine Corps Command and Staff College, where he was a distinguished graduate and completed the Masters of Military Studies program.
 
From 2019 to 2021 Major Kronjaeger served in 3D Light Armored Reconnaissance Battalion as the Executive Officer. 
 
From 2021 to 2023 Lieutenant Colonel Kronjaeger served as the Operations Officer of 5th Marine Regiment, and deployed to Australia in 2022 where the Regimental HQ served as the MAGTF Command Element of Marine Rotational Force - Darwin. 
 
In 2023 Lieutenant Colonel Kronjaeger served in the 1st Marine Division G-3, then transferred to 1st Light Armored Reconnaissance Battalion to assume command. 
 
Lieutenant Colonel Kronjaeger's personal awards include the Meritorious Service Medal, Joint Service Commendation Medal with oak leaf cluster in lieu of second award, and Navy and Marine Corps Commendation Medal with two gold stars in lieu of third award.