Asia was a primary destination to acquire herbs or spices in the medieval times directly, bypassing the Oriental trade route. Without refrigeration or proper preservation at that time, herbs and spices were a must in cooking for flavoring or simply masking stale odors. As a matter of course, gold and precious stones were other objects to sail to the unknown places. Thus fleets of spice-herb-gold hunters initiated a new era of globalization in the 15th century. Asian spices or herbs were a magnet to draw the western interest, yielding the current world geography and demography as a result.
The current spices or herbs, most of them, were brought back to the old continent, becoming inseparable parts of the western cuisines. Here is no intention to elaborate on these individuals but rather focusing on the recent arrivals or my interest which appear more often in our eating today.
My favorite story of spices or herbs is that of beer. Beer has been our major liquid staple of grains for centuries. Beer made the pyramids, as you know. In order to avoid spoilage, many spices or herbs were tried in beer. Hops was the herb finally found most appropriate to deter spoilage and also to bring pleasant flavor several hundred years ago. Then IPA (Indian Pale Ale) could be carried into India from England over the equator due to high hopping rates. Spices or herbs are nothing to do with stylish sophistication of our cooking or personal preference. They have been a must in culinary.
Lemongrass is at top of my curiosity of the Asian herbs. It literally smells like lemon but has no citric acid or sour taste. Regarding limonene aroma, lemongrass and lemon fruit are very similar or almost the same while the former gives no acid. You may say, though, lemongrass tastes a little bit grassy and lemon fruity, which may be a bias of respective origins. Their use depends whether or not acidic taste is needed. Minced lemongrass can be used in the place of lemon peel zest and its stick in a drink also. For orange-lemon chicken, lemongrass may be good if not much acidic taste is preferred. You may buy it at gourmet grocery stores or farmers markets. Or, you may grow in a pot yourself.
Cilantro (for plant or leaf), coriander (for seed), or Chinese parsley is the same, used in salad or dishes as well as a garnish. Its aroma-flavor is not easy to describe but it is unique anyway. To me, it tastes like something of vegetation growing in a dump place behind the house or a faint sensation of toothpaste in the morning. Some like it, whereas other do not like at all. Most Southeastern Asians from Vietnam, Thailand or China use it routinely, but not much by conservative Koreans or Japanese. Cilantro (not much coriander) may be the herb to divine like and dislike most.
Spices and herbs for seafood are still behind a veil, to me. Fish and seafood are often eaten by broiling over heat or cooking in a soup promptly after a catch. It may be a reason for the least use of herbs. Asian herbs may contribute something beyond fennel, rosemary or the current ones. Wasabi (true wasabi plant, not powder or tubed), sansho (mountain pepper in translation), shiso (red or green Perilla), etc. may be among unique options not only for serving as garnish or sauce for ceviche or sashimi but also in broiling or pan-cooking. Sansho (young leaves or seed-grains) in particular will bring an eye-opening flavor. Oh, do not forget ginger, which is under used, making many dishes beyond the Asian. Balance with other ingredients, congeniality, is a key to using Asian herbs-spices in your cooking-eating. Asian spices and herbs would bring about something to boost your creativity.