Fashion is an ever-evolving domain with trends coming and going like the seasonal ebb and flow. But amid this dynamic landscape, denim has stood the test of time. There's an inherent versatility to denim that has made it a universal fashion staple, transcending continents, cultures, and classes. Regardless of the trend du jour, jeans continue to rule wardrobes worldwide. Let's demystify the enduring popularity of this denim trend.

Born in the mid-19th century to clothe the Californian gold-miners, denim was initially recognized for its durability. Levi Strauss transformed a simple workers' fabric into the world's most iconic garment: Blue Jeans. But it's not just its rugged, hard-wearing characteristics that have endeared denim to the masses – It's its democratic appeal that transcends social strata.

There's a sheer democracy about jeans that taps into the universal desire for comfort, practicality, and style. It's an ubiquitous garment that everyone from cowboys to rock stars, hip-hop artists to presidents have embraced. It's the everyman's fashion piece, oblivious to the wearer's social status or wealth. A pair of well-fitted jeans has the potential to blur social lines and be a statement of equality.

Styles come, and styles go, but jeans persist, often adopting and evolving to reflect popular culture. The 1950s saw jeans becoming a symbol of teen rebellion thanks to Hollywood stars like Marlon Brando and James Dean. The hippie movement of the 60s and 70s saw denim becoming a canvas for self-expression – bell-bottoms, embroidered jeans, and patchwork patterns came into vogue. Then came the second wave of rebellion with the advent of punk and grunge in the 80s and 90s, which popularized ripped jeans and acid washes. 

Today, you'll find an abundance of styles to cater to every aesthetic – be it the skinny jeans favored by Millennials, the high-waisted 'mom jeans' making a comeback among Gen Z consumers, or the universally flattering straight cut. No two people wear their jeans the same way, with the fabric molding itself to the wearer's life and personal style. 

Denim's versatility extends to its pairing capability. Pair it with a simple t-shirt for a casual day out, a blazer for a chic street style look, or a sequined top for a party-ready outfit. Dress up your jeans with heels or dress them down with sneakers. The possibilities are limitless, and therein lies the secret of denim's enduring appeal.

Moreover, denim sustainability has taken center stage in recent years, with brands adopting more ethical manufacturing practices to cater to more environmentally conscious consumers. Denim has evolved beyond being merely a fashion statement to becoming a symbol of eco-conscious lifestyle.

In the face of the fast-fashion epidemic, denim tells a slower, more sustainable tale. A good pair of jeans is designed to last, shaping itself to the wearer's contours while aging gracefully. It's a garment that rebels against the 'wear and discard' culture, encouraging wearers to own and cherish their jeans for years.

In conclusion, unravelling the persistent lure of denim, its journey comes full circle. From its humble beginnings as miners' uniforms to becoming a symbol of rebellion, a canvas for creative expression, and a beacon of sustainable fashion, denim has successfully woven itself into the fabric of global culture. Its chameleonic nature, democratic appeal, versatility, and evolving sustainability have ensured that no matter how fashion progresses, it's still all in the jeans.

The enduring popularity of denim can be attributed to several factors:

1. Versatility: Denim’s all-occasion appeal sets this fabric apart from other fashion staples. It is equally suitable for casual and more dressed-up events. From basic blue jeans to embellished jean jackets, the ways of donning denim are innumerable and continue to evolve with changing fashion trends.

2. Durability: Denim, by its nature, is a sturdy fabric. Its durability ensures it can withstand regular wear and tear, a quality that has made it favorable for daily use over the years. Unlike several fashion trends that lacked practicality, denim offers robustness along with style.

3. Variety and Appeal: Denim is incredibly adaptable to different cuts, styles, and shapes, which contributes to its timeless appeal. Throughout history, we have seen many versions of denim pants, like high-waisted vintage styles or flared jeans from the 70s, skinny jeans that swept the early 2000s, or the more recent mom and boyfriend jean styles. Each trend echoes the fashion sentiment of its time, yet each continues to remain relevant in different sartorial contexts today.

4. Universal Appeal: Denim is virtually borderless. Its popularity crosses continental boundaries, making it a global fashion icon. Regardless of one’s cultural or social background, most people own some variant of a denim garment.

5. Democratic Fashion: Denim does not discriminate its wearers based on social class. It's worn by everyone: from factory workers to celebrities, teenagers to adults, denim is an indispensable cloth in almost everyone's closet around the world.

6. Nostalgia and Rebellion: Denim has historically been associated with rebellion, rebellion, social change, and youth culture. It is also seen as a return-to-roots fabric choice that has a nostalgic factor. Those cultural connotations keep denim relevant throughout the years.

7. Sustainable Fashion: With increasing environmental consciousness globally, the fashion industry faces criticism for unsustainable practices. In contrast, a pair of jeans is often a long-term investment, standing up to years of wear, and the call for sustainable denim has prompted many brands to reconsider their manufacturing practices. This emphasis on sustainability has given denim a positive contemporary relevance, keeping it in vogue.

In short, denim's indomitable popularity lies in its multifaceted approach: the fabric is resilient, versatile, and adapts to the changing tides of fashion while offering a nod to nostalgia and the past. It stands as a symbol of everyman's fashion, transcending geographic and social barriers, and remains appealing to the style conscious and casual dressers alike.