IntelliJ Spring MVC @RequestMapping Not Registering

I've been trying to reintroduce myself to Spring MVC @RequestMapping and working with Java in IntelliJ after 5 years away from Java and having primarily used Netbeans for any development. My last experience with Java was with Netbeans helping manage a Maven build.

I had my @RequestMapping annotations set up, and IntelliJ is launching Tomcat directly (vs. deploying to an already running instance). I created my *-servlet.xml configurations, and had my .jsp files placed properly. Everything seemed to be in good shape and compiling fine, but the routes I specified we not showing up with the project was run.

Eventually, I went to Build -> Build Artifacts -> ...:war:exploded -> Edit... and went the Project Settings -> Artifacts tab and noticed "Library 'org.springframework:spring-web:4.3.13-RELEASE' required for module '...' is missing from the artifact". Upon clicking "Fix" and adding the dependency. Some combination of that dependency and 'org.springframework:spring-webmvc:4.3.13-RELEASE' missing prevented the org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping.registerHandler from processing my @RequestMapping annotations.